The Engineering Projects

Home Security System using Arduino UNO in Proteus

Hello friends, I hope you all are doing well. In today's tutorial, we are going to design a Home Security System using Arduino UNO in Proteus software. It's the most commonly designed engineering project, especially in electrical, electronics and mechatronics engineering. Normally engineering students design it as a semester project during their engineering course.

So, today we will design a home security system from scratch in Proteus software. I have given the complete project below to download but I would suggest you to design it on your own so that you could understand it better. So, let's get started:

Where To Buy?
No.	Components	Distributor	Link To Buy
1	Battery 12V	Amazon	Buy Now
2	Buzzer	Amazon	Buy Now
3	LM7805	Amazon	Buy Now
4	OptoCoupler	Amazon	Buy Now
5	Relay	Amazon	Buy Now
6	Keypad 4x3	Amazon	Buy Now
7	LCD 20x4	Amazon	Buy Now
8	Flame Sensors	Amazon	Buy Now
9	MQ-2	Amazon	Buy Now
10	PIR Sensor	Amazon	Buy Now
11	Arduino Uno	Amazon	Buy Now

Home Security System: Project Description

• Before going into the detail, let's first download the complete Proteus Simulation with Arduino Code, by clicking the below button:

Home Security System using Arduino UNO in Proteus

Let me first give you a detailed project description i.e. what we actually want to design? We want to build a Home Security Project, which should follow these security protocols:

• Fire alarm: It should be able to detect the fire and sound an alarm to alert everyone at home.
• Smoke alarm: It should detect the gas(smoke) and turn on the alarm(if detected).

The above-mentioned security protocols will be followed 24/7. Moreover, there will be two security modes in the project, named:

• Secure Mode.
• Normal Mode.

Let's have a look at both of these modes, one by one:

1. Secure Mode

• This mode should be selected, when owners want to completely secure their home i.e. they are leaving home or while sleeping at night.
• If the Secure Mode is selected, the project should follow the following security protocols:
  • Intruder Detection Alarm: It should detect the presence of any human being in the occupied premises.
  • Windows Security Alarm: If someone tries to break through the windows, the project should sound an alarm.
  • Door Security Alarm: If any intruder tries to break through the main door, it should again sound the alarm to alert everyone.

2. Normal Mode

• This mode should be selected, when owners are at home and just want to take the basic security measures.
• In this mode, only the Fire Alarm & Gas Alarm will work, while all other alarms will remain on standby.

Other Features

• There should be an LCD, to display values of all parameters.
• It should have a buzzer to generate an alarm, in case of emergency.
• There should a Push Button to make switches between these security modes.

Here's the final simulation, which we are going to design in today's lecture:

So, these are our requirements, which we want to achieve in this Home Security Project. Now let's have a look at the components selected for this project:

Home Security System: Components Selected

Now let's have a look at the list of components, which I have selected for this Home Security Project. I will also briefly explain the purpose of using each component.

1. Arduino UNO

• As clearly it's an Embedded Systems Project, so first of all we need to select a Microcontroller for our project.
• As I have mentioned earlier, we will use the Arduino UNO Microcontroller board for designing this project.
• Arduino UNO will act as the brain of the project and will control all sensors and modules.

2. Flame Sensor:

• A flame sensor is used to detects the presence of fire.
• The sensor basically consists of a photo-diode that detects the Infrared rays that emit from the fire. When it detects a fire, its output goes HIGH.

3. Gas Sensor (MQ-6)

• MQ-6 Gas Sensor is used to detect the concentration of gases in the environment.
• The sensor produces a potential difference proportional to the concentration of the particular gases.
• The type of gas that it detects depends upon the material used in the sensor.
• There are many gas sensors available in the market i.e. MQ-2, MQ-3, MQ-4 etc.
• These sensors are available as ready-made modules for easy interfacing with the microcontroller.

4. PIR Sensor(HC-SR501)

• HC-SR501 PIR sensor is used to detect any human being(intruder) in the Secure Mode.
• It detects the IR radiations from the human movement & generates a pulse on its output.
• The time period of the pulse could be varied by using the potentiometer on the sensor.

5. Vibration sensor(SW-420)

• The SW-420 vibration sensor is used to detect any forced entry through windows.
• In Secure Mode, if someone tries to open the window, the sensor will detect vibrations and will send a HIGH signal to the microcontroller.

6. Infrared Sensor

• An infrared sensor will be placed at the door and someone tried to enter through that door, the sensor will detect it.
• It consists of an IR transmitter and a photo-diode that are placed close to each other.
• If any object movement occurs in front of the sensor, the IR rays hit the object and return back with a particular angle called incident angle.
• This pulls the comparator output to ground or logic LOW.

7. LCD 20x4

• LCD 20x4 will be used for displaying the values of all these sensors.
• It will also display useful information i.e. which mode is selected.

8. Buzzer

• A small 5V Buzzer is used to sound the alarm.

9. LM7805

• LM7805 is a voltage regulator and is used to convert voltage from 12V to 5V.
• Power sources(i.e. battery, adapter etc.) available are normally 12V, as it has become a standard.
• Moreover, many components also operate at 12V like a buzzer or DC motor.
• While microcontrollers and sensors work on 5V, so in Embedded projects, it's quite necessary to design a voltage regulator from 12V to 5V and in some cases 3.3V.
• I normally prefer LM7805 for converting voltage from 12V to 5V.

10. Resistances(1kohm)

• We need to use a few resistances of 1kohm.

11. Small LED

• We will also use a small LED for power indication.

12. Capacitors(100uF)

• We will also use few capacitors of 100uF, as it removes any noise/ripples.

So, these are the components, we are going to use for designing Home Security System. Now let's get started with designing the Proteus Simulation:

Proteus Simulation of Home Security System

As I have told you earlier, I am going to use Proteus software for designing this project. Proteus is an excellent simulation tool, where we will not only design the circuit of this project but will also test its output. I always design my programming algorithms on simulations as working on real hardware is too time-consuming. You should remove all your programming bugs in simulation and once confirmed then design your project in real hardware. So, let's start:

Install Proteus Libraries

• Arduino boards & sensors' modules are not available in the Proteus components list.
• So, first of all, we need to install these Proteus libraries:
  • Arduino Library for Proteus.
  • Flame Sensor Library for Proteus.
  • Gas Sensor Library for Proteus.
  • PIR Sensor Library for Proteus.
  • Vibration Sensor Library for Proteus.
  • Infrared Sensor Library for Proteus.
• Adding these libraries is quite simple, you just need to place their files in the library folder of Proteus software.
• If you got any issues, then read this guide on How to add a Library in Proteus 8.

Once you added all the libraries, now open your Proteus software.

Designing Circuit Diagram in Proteus

• Now we need to design a circuit for our project, so select these components from Proteus Components Search Box.
• First of all, let's design the voltage regulator circuit using LM7805, which will be simply converting the voltage from 12V to 5V.

• As you can see in the above figure, I have used 12V Battery, while the output of LM7805 is showing 5V and I have also placed an LED for power indication.

LCD Interfacing with Arduino:

• Next, we need to interface 20x4 LCD with Arduino UNO, so design the circuit as shown in the below figure:

Next, we need to interface five sensors with Arduino UNO, so let's add them to our Proteus simulation:

Sensors Interfacing with Arduino:

• These are simple digital & analog sensors and are all powered up at 5V.
• So, simply connect them as shown in the below figure:

• The Flame Sensor is connected to pin A0 of Arduino UNO.
• Gas Sensor is connected to pin A1 of Arduino UNO.
• PIR Sensor is connected to pin A2 of Arduino UNO.
• The Vibration Sensor is connected to pin A3 of Arduino UNO.
• The Infrared Sensor is connected to pin A4 of Arduino UNO.

For simulation, ensure all hex files are uploaded to each sensor for proper working. You can upload the source code hex file to the Arduino, by pressing Ctrl+E or by right click --> Edit properties.

Buzzer & Push Button:

• Finally, we need to add the Buzzer to sound the alarm in emergency cases, I have connected it to Pin A5 of Arduino UNO.
• I have also connected a push-button for switching the modes, connected to Pin 7 of Arduino UNO, as shown in the below figure:

• Here's the image of the complete Proteus Simulation for Home Security System:

Now let's design the Arduino programming code for Home Security Project:

Arduino Code for Home Security System

In the previous section, we have designed the Proteus simulation of the project, now let's design its Arduino Code to make it alive. Let's get started:

Initialization LCD Arduino Code

• First of all, we need to define all our variables, as you can see in the code shown in the right figure.
• I have included the Liquid Crystal Library, which is used to operate LCD.
• Next, I have defined all my sensors to the respective pins and then initialized boolean variables for storing the output of sensors.
• In the Setup loop, I have made the sensors' pins input pullup using the pinMode Arduino command.
• Finally, displayed an initialization message on the LCD screen i.e. "Home Security System using Arduino UNO By TEP".
• The message will display for around 1 second and then LCD will be cleared and the SensorDisplay function will be called, which will simply write sensors' names on the LCD screen.
• Now compile your code and add the hex file in Arduino UNO and run your PRoteus simulation.
• If everything goes fine, you will get results as shown in the below figure:

So far, we have just displayed the sensor's names, now let's read the sensors' data in the loop section:

Reading Sensors' Data

• In the loop section, first of all, we need to read the sensors' data using the digitalRead command, as shown in the code.
• After reading the sensor's data, I have called the SensorValues function, in which I have placed a check on each sensor's value and updated it on LCD.
• It's quite straightforward code, if the sensor is giving HIGH output, I am displaying Yes on LCD and if it's LOW, I am simply printing No.
• We haven't yet defined the modes, so the project will keep on reading the sensors and will display their respective value in the LCD.
• As you can see in the below figure, if the TestPin of the sensor is HIGH, its respective value on LCD is showing "Yes" and if it's LOW then "No" is written.
• Now, if you change any sensor's value, its respective value on LCD will be updated.

So, we have successfully interfaced our sensors with Arduino UNO and now it's time to add operational modes to our project.

Two Operational Modes

• As I mentioned earlier, we need to add two operational modes in our project, and the push button will be used for conversion from one mode to another.
• So, I have simply added an If loop in my code, as shown in the figure on the right side.
• In normal mode, I have simply displayed the name of the mode at the first line of LCD.
• While in secure mode, I am checking if either of the sensors goes HIGH, simply turn ON the Buzzer.
• Although, you won't be able to hear the Buzzer sound in the below figure, but you can see Buzzer's Pin is HIGH because two of the sensors are giving a response. Check the video for Buzzer working.

• We normally need to use an optocoupler or relay driver in between the buzzer and microcontroller as buzzers normally operate at 12V, but 5V buzzers are also available.
• Here's the complete Arduino Code:

/* * All rights reserved to TEP www.TheEngineeringProjects.com */ #include const int rs = 12, en = 11, d4 = 5, d5 = 4, d6 = 3, d7 = 2; LiquidCrystal lcd(rs, en, d4, d5, d6, d7); #define Flame A0 #define Gas A1 #define Pir A2 #define Vib A3 #define Ir A4 #define Buzzer A5 #define Switch 7 boolean Fire, Smoke, Intruder, Window, Door; boolean Mode = false; void setup() { pinMode(Flame,INPUT_PULLUP); pinMode(Gas,INPUT_PULLUP); pinMode(Pir,INPUT_PULLUP); pinMode(Vib,INPUT_PULLUP); pinMode(Ir,INPUT_PULLUP); pinMode(Switch,INPUT_PULLUP); pinMode(Buzzer,OUTPUT); lcd.begin(20,4); pinMode(Buzzer, OUTPUT); lcd.setCursor(0,1); lcd.print("HOME SECURITY SYSTEM"); lcd.setCursor(0,2); lcd.print(" USING ARDUINO UNO "); lcd.setCursor(7,3); lcd.print("By TEP "); //delay(700); lcd.clear(); SensorDisplay(); } void loop() { Fire = digitalRead(Flame); Smoke = digitalRead(Gas); Intruder = digitalRead(Pir); Window = digitalRead(Vib); Door = digitalRead(Ir); Mode = digitalRead(Switch); SensorValues(); if(Mode==false) // Normal mode { lcd.setCursor(4,0); lcd.print("Normal Mode"); } else // Secure Mode { lcd.setCursor(4,0); lcd.print("Secure Mode"); if((Fire == HIGH) || (Smoke == HIGH) || (Intruder == HIGH) || (Window == HIGH) || (Door == HIGH)){ digitalWrite(Buzzer, HIGH); }else{ digitalWrite(Buzzer, LOW); } } } void SensorDisplay() { lcd.setCursor(0,1); lcd.print("Fire:"); lcd.setCursor(10,1); lcd.print("Smoke:"); lcd.setCursor(0,2); lcd.print("Door:"); lcd.setCursor(10,2); lcd.print("Window:"); lcd.setCursor(0,3); lcd.print("Intruder:"); } void SensorValues() { if(Fire == true){ lcd.setCursor(6,1); lcd.print("Yes");} else{ lcd.setCursor(6,1); lcd.print("No ");} if(Smoke == true){lcd.setCursor(17,1); lcd.print("Yes");} else{lcd.setCursor(17,1); lcd.print("No ");} if(Intruder == true){lcd.setCursor(11,3); lcd.print("Yes");} else{lcd.setCursor(11,3); lcd.print("No ");} if(Window == true){lcd.setCursor(17,2); lcd.print("Yes");} else{lcd.setCursor(17,2); lcd.print("No ");} if(Door == true){lcd.setCursor(6,2); lcd.print("Yes");} else{lcd.setCursor(6,2); lcd.print("No ");} }

Future Scope of Home Security System

• Embedded has taken over the whole world because of its user-friendliness and low cost.
• Instead of hiring security guards(which is quite expensive), now smart homes in modern societies are equipped with such home security systems.
• Modern Home Security systems are even linked with local police or security agencies for emergency help.
• Moreover, these security systems are not bound to homes only, nowadays offices, banks, shopping malls etc. are all equipped with such smart security systems.

Future Work on Home Security System

• Today, we have designed a very simple Home Security System, where we interfaced few sensors and have only placed a Buzzer.
• We will continue this project and will add smart features to it.
• Let's have a look at few features, which we can add to this project:
  1. We can interface the GSM module to send messages, in case of emergency.
  2. We can add more sensors i.e. ultrasonic sensors, different types of Gas sensors in it.
  3. We can also improve our code by using interrupts instead of polling.
  4. We can also add a camera for facial recognition.
  5. To improve the security, we can add a keypad and only authorized persons will have the access to enter.
  6. The fingerprint sensor can also be used for identification purposes.

No matter what happens, you should put safety first. Even a great security system won’t ensure full protection, which is why you might want to consider secondary measures. Hiring fire watch security will assist you on a daily basis, performing tasks that machines cannot. These veterans will protect your home or office, addressing potential hazards as they appear.

So, that was all for today. I hope you guys have enjoyed today's project. If you have any questions/queries, please ask in the comments and I will try my best to resolve them asap. Thanks for reading, take care. Bye :)

Periodic Table of Elements: Definition, Groups & Trends

Hello friends, I hope you all are doing great. In today's tutorial, we will have a look at a detailed overview of Periodic Table. Understanding the Periodic Table is one of the nightmares everyone had once in a lifetime, don't fret! I was one of those people too. Today I would be breaking down this complex topic into smaller digestible chunks. Before diving deep into the topic let me introduce you to the fact that atomic number is more reliable than the atomic mass of an element, every element has a fixed atomic number and it increases by a value of 1 with every element in the modern periodic table, that is the reason why we use Atomic Number instead of Atomic Mass as the base of the modern periodic table.

History of Periodic Table

Rome wasn't built in a day, in the same way, the modern periodic table isn't the product of a single effort from a chemist or two, it took two centuries to complete. The older version of periodic table was based on Atomic Masses by Dimitri Mendeleev, Many scientists contributed to the formation of the periodic table such as:

• Doberiner presented the idea of Triads when he observed the relationship between the atomic masses of three elements. Within a Triad the central element had the atomic mass equal to the average of two corresponding elements.

• Newlands proposed the Law of Octaves in 1864 when he observed the repetition of properties in every eighth element, when elements were arranged in an order of increasing atomic masses.

Later on, after the discovery of atomic numbers by Henry Mosley in 1913 and some new elements modern periodic table is now based on the increasing order of atomic numbers which was proposed by Henry himself when he discovered atomic numbers. Let's have a look at the proper definition of periodic table:

Periodic Table Definition

Let’s start with its basic definition;

• Periodic Table is the tabular arrangement of elements in the order of increasing atomic numbers, Hydrogen having the smallest atomic number, meanwhile, Oganesson having the highest atomic number of all.
• The vertical columns from top to bottom are called Groups in the periodic table, which are 18 in number.
• The horizontal rows from left to right are called Periods. There are 7 periods in the Periodic table.
• Here's the image showing the modern Periodic Table:

Arrangement of Modern Periodic Table

The periodic table has 118 elements till now, we can figure out a lot of things about an element just by looking at it, such as:

• Atomic weight is present at the top right corner.
• Atomic number is at the top left corner.
• Electronic configuration of valence shell can be seen at the bottom left corner.

Consider the following example for better understanding:

Groups and Periods

As I have mentioned earlier, elements are arranged in an order of increasing atomic number in the form of rows and columns called periods and groups respectively. When I was a student I was always confused about period and group, so here's a trick if you're struggling too, just cram it as " top to bottom in a group" so whenever you'll think of a group you'd have an idea what exactly you're thinking about.

Blocks in Periodic Table

• Periodic table can be divided into four blocks, s, p, d and f.
• Have you ever thought why they are named s, d and p? They could have been named a, b, c or d! Let me figure this out for you:
• Blocks are named after the electronic configuration of valence electrons.
• For example, all s block elements have their valence electrons in s subshell and same goes for p block elements, interesting! Isn't it?

Groups in Periodic Table

There are 18 groups in periodic table which are named as:

• Group 1 comprising of Alkali Metals
• Group 2 having Alkaline Earth metals
• Group 3 – Group 12 housing Transition elements
• Group 13 housing Boron family
• Group 14 with Carbon family
• Group 15 containing Nitrogen family
• Group 16 having Oxygen family
• Group 17 with Halogens
• Group 18 containing Inert or Noble gases

Group 1 of Periodic Table: Alkali Metals

• This is the very first group of the periodic table and its members are called Alkali metals with elements Hydrogen being the lightest having an atomic number of 1, succeeded by Helium, Sodium, Potassium, Rubidium, lastly Cesium and Francium in the family.
• You might have thought why they are called alkali metals? Upon reacting with water these metals give strong alkalis, naming them as alkali metals. 

Physical Properties of Alkali Metals:

• Physically they are shiny, lustrous and sleek in appearance.

Chemical Properties of Alkali Metals:

• Alkali metals are highly reactive and their reactivity increases down the group.
• All of them have low Ionization energies so it is easier for them to lose an electron.
• They are mostly found in an oxidation state of +1.

Group 2 of Periodic Table

• Group 2 elements were discovered by Humphry, it contains highly reactive elements which result in oxides upon reacting with oxygen, and these oxides when dissolved in water produce strong alkali solutions taking their name as Alkaline Earth Metals.
• Alkaline earth metals have Beryllium, Magnesium, Calcium, Strontium, Barium and Radium in the group with an order of increasing atomic number.
• They are very reactive and so are considered strong reducing agents. Do you know what a reducing agent is?

“A reducing agent is a chemical species which can lose electrons easily in a chemical reaction and hence oxidizes itself”. Chemical Properties of Alkaline Earth Metals:

• They are highly reactive in their natural forms being strong reducing agents.
• They can easily become a cation with 2+ charge by losing two electrons from their outermost shell.

Physical Properties of Alkaline Earth Metals:

• They are highly abundant in nature.
• They have a shiny appearance and are often silvery-white in color.
• They have a lot of commercial applications.

Group 3-12 of Periodic Table

• This group comprises of the d and f block elements which are found in the center of the periodic table and are famously known as Transition Elements.
• d block elements are called outer transition elements meanwhile f block elements are called inner transition elements despite the fact that they occupy totally opposite places in the periodic table.
• You might have thought why d and f block elements are called transition elements?

Here is a simple answer to the question, the d and f block elements have their properties in between s and p blocks elements, some of them show the characteristic behaviors of s block that is Group 1 and 2 elements by losing electrons meanwhile some of the elements resemble p block elements by gaining electrons during a chemical reaction in this way they take their name as transition elements. Following are the families found in the transitional groups:

• Group 3 has Scandium family.
• Group 4 houses elements like Titanium making them Titanium family.
• Group 5 is called Vanadium family.
• Group 6 has Chromium family having very famous members like Tungsten.
• Group 7 is Manganese family.
• Group 8 is the Iron family, who is not familiar with this super famous element? We all have been hearing it since childhood.
• Group 9 is the Cobalt family.
• Group 10 has Nickel family with its famous members like Platinum, you all have heard of Platinum rings and bands right?
• Group 11 has been crowned by Copper along with Silver-Ag as its succeeding member.
• Group 12 lastly forms the Zinc family with its ever useful and renowned member Mercury which is the only metal found in the liquid state on room temperature, that's is the reason it is commonly used in Thermometers! 

Lanthanides and Actinides:

• These are f block, inner transitional elements with unique properties as clearly visible by their names.

Actinides have the following properties:

• Atomic number ranges from 89 to 103
• Radioactive in nature
• Valence electrons in 5f orbitals
• Oxidation state can be up to +6

Lanthanides have the following properties:

• Atomic number ranges from 57 to 71
• Valence electrons are present in 4f orbitals
• They are not radioactive in nature
• Can maximally go up to +4 oxidation state

Chemical Properties:

• They are excellent conductors of electricity because of the formation of electronic pool in their structure, when I was in school I used to think of the best conductor of all the Transition Elements, at that time I didn't have Google so I could have searched, I have got to know now, it's Silver which is the best of all these metals in terms of conductivity.
• They form complex ions and colored compounds as a product of their chemical reactions.
• They have high melting and boiling points. 

Physical Properties:

• These groups have metals which are Malleable and Ductile, which in simple terms mean; they can be turned into sheets and wires.
• In terms of physical appearance they have shiny and lustrous appearance, if you forget in any case the properties possessed by these groups just recall that Silver is a transition metal with a shiny, lustrous appearance and can be turned into jewelry too. 

Group 13 of Periodic Table

• Group 13 elements are also called Boron family with other elements like Aluminum, Gallium, Indium, Thallium and Nihonium in the order of increasing atomic number, Boron being the smallest and Nihonium being the largest element but synthetic in nature.
• Group 13 elements are also called Triels or trivalent because of the presence of three electrons in their valence shells.

Chemical Properties and Usage:

• You must have been thinking about the chemical properties of this group! So let me tell you, they are highly abundant in nature and reactive too they can react with hydrogen, oxygen and halogens forming hydrides, oxides and halides respectively.
• Boron family has isotopes too which have wide applications in medical field.
• From Boron being used in ceramics to the Aluminum which is the most abundant metal of earth crust being used in construction and metal works, Indium and Gallium are not lesser than any of the other group members, they have a lot of commercial applications too.
• Thallium is used in the production of poisons for killing reptiles and rodents.

Group 14 of Periodic Table

• This is known as the famous Carbon family with its top most members as Carbon and Silicon.

Physical Properties and Usage:

• When thinking of Carbon one must recalls the chemical reactions in Organic Chemistry which were never an easy pill to swallow! Phewww! Carbon has the unique bonding ability to form long chains which is called “Catenation”, all thanks to catenation we have another branch of chemistry known as Organic chemistry. Not only organic chemistry, but Diamond and Graphite are also the gifts of Carbon being their allotropes.

• Next to Carbon is Silicon which is one the most abundant elements on the planet Earth and is commercially used in the formation of semiconductor diodes and chips used in various technological devices. Germanium is used in the formation of semiconductors as well.
• Who's not aware of lead and tin? Both of the elements are used commercially because of their stable nature in the formation of cans, nuts and bolts.

Chemical Properties of Carbon Family

• Carbon family has four electrons in its valence shells which results in covalent bonding.
• Covalent bonding is the reason of their high melting and boiling points.
• All of the group members form hydrides, oxides and halides reacting with hydrogen, oxygen and halogens respectively.
• They are usually found in the oxidation states of +3, -4 and +4.

Group 15 of Periodic Table

• Group 15 is also known as the Nitrogen family or Pnictogens.
• The name Pnictogens points to the ability of nitrogen to choke in the absence of Oxygen. Other members of the group include Phosphorus, Arsenic and Bismuth.

Reactivity:

• Nitrogen and Phosphorus act as non-metals whereas Arsenic and Antimony have proven themselves to be metalloids, meanwhile the last member Bismuth is a metal.
• They form covalent compounds due to the presence of five electrons in their valence shell and are mostly found in the oxidation state of +3 or +5

Usage:

• Nitrogen is found abundantly in nature, you might have thought of it earlier while studying Nitrogen Cycle in your school textbooks. Chefs using liquid nitrogen to freeze a dessert instantly has always fascinated me, it is due to its unique ability to stay non-reactive at room temperature. Nitrogen is used in fertilizers and has countless commercial applications.
• Meanwhile other members of the family are not less than any other element, Phosphorus is highly flammable and used in manufacturing explosives and fireworks and has three forms red, black and white.
• Arsenic being poisonous founds its use in fertilizers.
• Bismuth is used in pharmaceutical industry for production of several beneficial drugs.

Group 16 of Periodic Table

• Elements of group 16 are also called Chalcogens, as interesting as the name sounds, the reason behind the name lies in the ore forming ability of these elements.
• Oxygen, Sulphur, Selenium, Tellurium and Polonium are the members of this groups.

Chemical Reactivity:

• Chemical reactivity increase down the group with the increase in atomic number.
• Total number of valence electrons are six in the family which encourage covalent bonding, as it is very difficult to loose six electrons meanwhile gaining two electrons to complete the octet would be easier, isn't it?
• Oxidation state of -2 is most common among the group, Sulphur can exist as +4 and +6 as well.

Usage:

• Oxygen is the most abundant one, now a days we have seen an enormous demand for clinical oxygen in Covid stricken patients, different types of oxygen is obtained by fractional distillation in plants under specific conditions, many industries such as steel mills use oxygen in their processes as well.
• Sulphur is found in the form of ores and is used in the formation of fungicides and several medicines.
• Selenium and tellurium are photoconductive meanwhile polonium is a rare radioactive metal.

Group 17 of Periodic Table

• Elements of the group 17 are called Halogens and are highly reactive, students often ask about the reason behind their unique name, so cracking it for you Halogen is a Greek word which has been derived from two words “Halo” meaning “Salt” and “Gen” means “to produce something”, the term collectively means “salt producing”.
• These elements are called halogens because of their salt producing ability when they react with an alkali metal. Halogens include Fluorine, Chlorine, Bromine, and Iodine.

Chemical Reactivity:

• Fluorine is the most reactive element of this group.
• All the halogens have seven electrons in their outermost shell so they can easily gain an electron in a chemical reaction. They have a usual oxidation state of -1.
• They are good oxidizing agents because of their higher electron affinities.

Physical Properties:

• Halogens turn into a darker color as we move from top to bottom in the group. Fluorine being pale yellow, meanwhile Chlorine has a greenish yellow tint, Bromine is found in brown color and lastly Iodine has a purple hue.
• First two elements are gases, Bromine is a liquid and Iodine exists as a solid at room temperature.

Usage:

• You must have watched a million ads on the television about fluoride toothpaste, yeah! It helps in preventing tooth decay. Fluorine has always been a fundamental part of dental industry.
• Chlorine is a bleaching agent and used to purify water as well especially in swimming pools.
• Bromine is used for water purification, pesticide production and in pharmaceutical companies as well.
• Using Iodized salt is a common practice in many countries, because it helps in improving growth and metabolism when used in appropriate amounts. Iodine is also used as a topical antiseptic agent.

Group 18 of Periodic Table

Elements of group 18 are also known as Noble gases, who is termed as a noble? A person who never mess around with anyone, same is the state of Noble gases, they're inert and don't react with anything because of the very obvious reason, can you guess? Yeah! You guessed it right. They have a complete octet, they don't have to reach out anyone to be stable. Noble gases include Helium, Neon, Argon, Krypton and Xenon. Physical and Chemical Properties:

• Noble gases are colorless and odorless in normal conditions.
• They have low melting and boiling points.
• Noble gases can be used as oxidizing agents under special circumstances.

 Usage and Applications:

• We all have seen ice cream cone as a lighting sign with popping colors outside the ice cream parlor, they're called Neon signs, the gas in them is not exactly neon every time but is always a Noble gas. All Noble gases give out their specific color when lighted.
• Helium balloons have also remained eye candy to every one of us in our childhoods as Helium gas is very light in nature that is the reason it is used for filling balloons.
• One of the latest applications of the noble gases are Excimers, these are the diamer forms of Noble gases and have wide applications in medical field. They help in eye surgery and myocardial repair.

Trends in the Periodic Table

In order to understand the trends found in the periodic table we must understand the term periodicity “Periodicity refers to the cyclical trend in the chemical and physical properties of the elements with increasing atomic number.” Periodicity help us understand and predict various trends among the family members of same group just like offspring from same parents have some general characteristics in common , they all may have blue eyes or black hair or anything in common as a family, families of the periodic table also have common characteristics in the similar ways.  Some of the periodic trends in the periodic table are;

• Atomic radii.
• Ionization energy.
• Electron affinity.
• Electronegativity.
• Shielding effect.
• Metallic and Nonmetallic  behavior.

Atomic Radii Trend in Periodic Table

• Atomic radii is one of the core aspects that can make the elements behave in a certain way in a chemical reaction.

Factors effecting the Atomic Radii:

• Atomic number
• Number of shells : As we move from top to bottom in a Group the atomic number increases, this gradual increase in the atomic number makes the atomic radii larger and larger by adding in a number of shells

Trend across the Group:

• When the atomic radii grows larger from top to bottom in a group, the hold of the nucleus on the valence electrons decreases.
• This decreased force on the valence electrons increases the reactivity of an element.
• So we can conclude that as we move towards the bottom an increase in reactivity of the elements can be predicted, why? Because they are less bounded by the nuclear forces and are free to react.

Trend across the Period:

• Similarly when moving left to right in a period , atomic radii decreases due to the decrease in atomic number and hence reactivity of the elements decreases , all thanks to strong grip of the nuclear forces on the valence electrons which pulls the electronic cloud towards itself.

Largest and smallest element With respect to Radius

• You might have thought which is the largest and the smallest element in terms of radius? Let me tell you, the smallest one is Helium meanwhile the largest one is Francium.

Exceptional Behavior:

• There are a few exceptions in the normal trend as well because all the five fingers can never be same.
• Ooxygen has a larger radius than its neighboring nitrogen all because nitrogen has seven proton in its nucleus meanwhile oxygen has eight so it has larger ionization energy value.

Ionization energy Trend in Periodic Table

Ionization energy can be defined as:

• "Ionization energy is the amount of energy required to remove the loosely bound electron from the outermost shell of a neutral gaseous atom in its ground state".

Factors effecting ionization energy:

• Atomic radius
• Shielding effect
• Increased atomic number

Trend across the Group:

• Ionization energy is mainly governed by the atomic radii, as we move from top to bottom in a group atomic radii increases, which results in a decline in effective nuclear charge.
• A declined effective nuclear charge and an increased shielding effect leads to the lesser binding force on the valence electrons, when the valence electrons have less nuclear force on them, what would happen? That would be easy to remove by giving a small amount of energy, this energy is called the ionization energy.
• Summing up we can say ionization energy decreases down the group as we move towards the bottom.

Trend across the Period:

• When moving across a period from left to right, the effective nuclear charge increases leading to a decrease in atomic radii, ultimately shielding effect also decreases, all these factors make it highly difficult to remove an electron rather they would prefer to gain an electron or two for stability.
• So we can say that ionization energy increases from left to right in a period. 

Types of ionization energy; There are two types of ionization energy

• First ionization energy
• Second ionization energy

Following is an example of first and second ionization energy:

• First ionization energy is the energy required to remove the electrons from a neutral gaseous atom.
• Second ionization energy refers to the amount of energy required for removal of an electron from the molecular ion or cation.

So here is an understandable clear fact which must not be missed in any way; second ionization energy is always higher than the first one. Let me explain why! It happens because of the increase of additional positive charge on the electronic cloud because of the removal of electron, nucleus tightens its grip on the valence shell, and hence a large amount of energy is required to remove an electron which is always higher than the first one.

Shielding effect Trend in Periodic Table

Before studying the shielding effect let's discuss what does a shield do? A shield masks or hinders the effect of any force applied to a body, when same principle is applied to an atom, we can define shielding effect as:

• "When the inner shell electrons shield the effect of nucleus, decreasing the effective nuclear charge on the valence electrons, then this phenomenon is called shielding effect".

Shielding effect decreases the effective nuclear charge experienced by the valence electrons. So now you must be thinking what is effective nuclear charge?

• "Effective nuclear charge is the average net positive charge experienced by an electron from its nucleus".

Trend across the Group:

• As the atomic number increases the number of shells in each atom also increase, with every additional shell there's a greater shielding effect on the valence electrons.

Trend across the Period:

• Shielding effect increases from top to bottom in a group meanwhile it remains constant from left to right in a period.
• The sole reason behind constant shielding effect from left to right is the same number of shells in all the elements residing in a period, no additional shell leads to constant shielding effect. Simple!

Electronegativity Trend in Periodic Table

Electronegativity can be defined as,

• "The ability of an atom to attract the shared pair of electrons partially or completely towards itself when bonded to another atom in a molecule".

Whenever we study covalent bonds we often talk about the poles, this is a polar covalent bond that is a non-polar one, you might have thought which causes this polarity within the molecules? So now you have your answer, electronegativity difference causes polarity in a molecule. Electronegativity values of certain elements have already been determined, the difference between their values i.e. the electronegativity difference help us predict the nature of bond, whether it would be ionic, covalent, slightly polar or moderately polar in nature. Factors effecting Electronegativity: Electronegativity of an element is effected by the following:

• Atomic number
• Number of valence electrons
• Shielding effect and effective nuclear charge
• Atomic radii

Trend across the period:

• In the periodic table electronegativity increases across the period when moving left to right, fluorine being crowned as the most electronegative element of all having the value if 4.
• All thanks to the strong grip of nucleus on the electronic cloud, which never lets anyone escape its grip!

Trend across the group:

• Meanwhile due to increase in atomic number and shielding effect, electronegativity decreases down the group, so these elements have lesser tendency to keep the shared pair of the electrons towards themselves so we can say that the left bottom elements of the periodic table can never be good keepers of the shared electrons.

Electron Affinity Trend in Periodic Table

Electron affinity is the opposite of Ionization energy which we have discussed earlier, ionization energy is the energy required for removal of an electron on the other hand electron affinity is the energy required for the addition of an electron to an atom.

• Electron affinity can be defined as “the amount of energy released when an electron is added to a neutral gaseous atom turning it into an anion.”

As energy is being released the process is exothermic in nature.

• Halogens have highest electron affinities in the periodic table
• Metals have lowest electron affinities in the periodic table.

Factors effecting electron affinity: Electron affinity is effected by the following:

• Atomic number
• Number of valence electrons
• Shielding effect and effective nuclear charge
• Atomic radii.

Trend across the Group:

• When we move from top to bottom in a group, atomic radii increases resulting in a weak nuclear charge on the valence electrons.
• So what you think now what would be the trend? I hope you can easily guess it by now! Yes you are right, electron affinity would decrease from top to bottom in a group.

Trend across the Period:

• From left to right in a period, effective nuclear charge never let anyone move astray like street animals, so it has strong hold on the valence shell, adding an electron releases a huge amount of energy which corresponds to higher electron affinity values increasing the electron affinity values gradually across the period.

Element with highest electron affinity:

• Chlorine has the highest electron affinity of all the elements even higher than fluorine because of its structural compactness as compared to fluorine.

Metallic Character Trend in Periodic Table

• Metallic character is one of the most interesting properties possessed by elements, as indicated by name, “metallic character is the ability of metal to lose electron during a chemical reaction.”
• Metallic character is observed due to the least ionization energy values of the metals which tend to loose electrons easily to remain stable rather than keeping them.

Electron pool theory: While discussing metallic character we must not forget electronic pool theory , Electronic pool theory is about the metallic character of the metals which tend to lose all their valence electrons turning it into a pool of electrons around a positive charge , this is the reason of their electrical conductivity, now you know! Trend across the Group: Metallic character increases down the group because of the following factors that come into play;

• Increased atomic number.
• Increased atomic radii.
• Lesser ionization energy.

In the presence of above factors, metals tend to lose electrons easily. Trend across the Period:

• From left to right in the periods metallic character decreases due to higher effective nuclear charge and smaller electronic clouds, so it is extremely difficult to lose an electron and exhibit metallic character.

Most and Least Metallic Elements:

• The most metallic of all the elements is Francium, meanwhile Fluorine is the least metallic or non-metallic element of the periodic table.

So that was all about periodic table and its groups with their brief introduction and general trends, I hope it helped you clear some general misconceptions we all have in our minds regarding the topic. See you with another topic soon, have a good day!

Traffic Light Simulation with D Flip Flop in Proteus

Hi Mentees! we hope you are doing great. Welcome to a super easy yet useful project based upon the simulation in Proteus. We are working on the Traffic Lights project that will work with the help of D Flip Flop. In this simple tutorial, you will be aware of the following concepts:

1. What are the Traffic Lights using D Flip Flop?
2. What is the role of D Flip Flop?
3. How does the circuit of D Flip Flop work in the Traffic Lights?
4. How can you simulate the circuit of Traffic Lights with D Flip Flop in Proteus?

In addition, you will find some important information about the Traffic Lights circuit in the DID YOU KNOW Sections. Let's start learning.

Traffic Lights with D Flip Flop

Who is not aware of the traffic lights? we all observe and use the Traffic lights on the road every day. But for the sake of the concepts, let's see the traffic lights technically.

"The Traffic Lights are the signaling devices that has an electronic circuit designed to control the flow of traffic at the roads by a specialized pattern of lights."

These traffic lights are positioned at road intersections ad pedestrian crossing and other positions where the traffic flow has to maintain. The Traffic Lights depends on an array of three lights with different colors that are connected electrically The whole system is packed into a metallic structure. The LEDs turn on and off with a special pattern that depends upon the circuit. Before moving forward, refresh the concepts of Traffic Light with the logical point of view. There are three lights in the Traffic Light Signals. These are:

1. Red
2. Amber
3. Green

The red light stays last for some moments. The circuit is designed so, we get the output from the Amber color light that coordinates with the red and green light and lasts for some time. In the end, we get only Green light. All these lights are formed as a result of the sequential logic of D Flip Flop and at the end, the output of two D Flip Flops are inserted into AND Gate. The output of the Green light depends upon the AND Gate and we found the light of green LED only when the output of both the D Flip Flops are HIGH.

Role of D Flip Flop in Traffic Lights

Have you ever thought about how does the traffic light blink at a specific time? We all follow the Traffic lights but today we'll learn that what does traffic light follows. The D Flip Flops are the logical circuits and we define the D Flip Flop as:

"The D Flip Flops a dual input is Flip Flop circuit that is designed to have the input at its D Terminal, regulates the signal with the clock edge pulses and shows the output at its two output terminals."

In the Traffic Lights, we use two D Flip Flops that are responsible for the switching of the lights in on or off conditions. The D Flip Flop is the combination of the S and R Flip Flops with an inverter with one terminal. but for  simplicity, we'll use the Integrated Circuit of D Flip Flop. Hence our circuit has only four components and we get a clean, easy and useful circuit that works automatically. The input Terminals are called CLK and D terminals whereas output terminals are denoted by Q and Q'.  The Truth Table for the D Flip Flop is given next:

Inputs		Output
CLK	D	Q	Q’
0	X	No Change
1	0	0	1
1	1	1	0

The X is called the don't care condition which means in this situation, the value of D does not matters. You can learn more about D Flip Flop in https://www.theengineeringprojects.com/2021/01/d-type-flip-flop-circuit-diagrams-in-proteus.html section. The output of the D Flip Flop is connected with each LED in the Traffic lights and hence we observe the on/off situations of Traffic Lights.

Working of Traffic Lights circuit with D Flip Flop

The working of the Traffic Light starts with the change in the pulse of the clock.

1. The Q' output of the D Flip Flop 2 gives the power to the Red Light of the Traffic Light.
2. When the clock is low, there is no change in the Q' terminal of the 1st Flip Flop then the Amber light is off.
3. With the clock pulses, the Amber light of the Traffic Light turns on.
4. When the clock is high, we get the output inverse of the D Flip Flop.
5. The output Q of the D Flip Flop1 and the Q' of the D Flip Flop 2 is fed into AND Gate.
6. We know the AND Gate is HIGH only when both of its terminals are HIGH.
7.  This output of the AND Gate is connected with the Green Light of the Traffic Light.

Circuit Simulation of Traffic Lights in Proteus ISIS

For the simulation of Traffic Light in Proteus, simply follow the easy steps coming next.

Devices required for the Traffic Lights

1. D Flip Flop - DTFF
2. Traffic Lights
3. AND Gate
4. Clock pulses - DClock
5. Connecting wires

• Power up your Proteus software.
• Click the "P" button.

• Write the names of 1st three devices given above one by one and choose them.
• Get D Flip Flop twice, And Gate and Traffic Lights from the pick library and arrange them on the working area.
• Go to Generation mode(from the sidebar) >DClock and set it just on left side of the 1st D Flip Flop.

• Connect all the components with the help of connecting wires.
• Connect the Traffic Light's red light with the output of 1st D Flip Flop, the amber light with the D Flip Flop 2 and the green light with the output of AND Gate.

• Pop the play button.

Does your Traffic Lights are working well? great! if not, then check the connection again. if you face any problem then share with us. Consequently, today we learned about the logic behind the Traffic Lights. We learned that with the help of D Flip Flop, one can easily design a circuit just using four simple devices. We saw the working of the sequential on/off condition of the Traffic Lights. Stay with us for more interesting circuits.

H-Bridge Circuit with 2N2222 Transistor in Proteus

Hey Learners! Welcome to The Engineering Projects. We hope you are doing great. Our team is working on transistors and today, we'll design a circuit for using the 2N2222 Transistor. In this chapter you will learn:

1. What is H Bridge with 2N2222 Transistor?
2. How do the 2N2222 Transistor works?
3. What is the working of H Bridge?
4. How can we run the circuit of  H Bridge in Proteus using 2N2222 Transistor?

By the same token, you will also learn important information about the topic in DID YOU KNOW Sections.

Introduction to H-Bridge

In electronic circuits, the direction of quantities like the flow of current, EMF, Electric field lines matter a lot. The H Bridge is used to control such motors through its specialized circuitry. The H Bridge is defined as:

"The H Bridge is an elementary circuit that ends the Motors to rotate in forward or backward direction according to the will of the user."

In this way, there is no need for the two motors in many cases. Only one motor can be used to accomplish the task instead of two.

DID YOU KNOW???

The most common, easy and interesting application of the H Bridge is in the robotics. The H Bridge is used to run the motors of the robots that are required to move the robot in the forward and backward direction.

The circuit of the 2N2222 H Bridge allows the current from the Direct Current source to flow from the required direction only and hinders the flow from the other direction.

Why we need the H Bridge

The direction of the moving of a motor paly a vital role in the output of that motor. The reason behind this is, most electric motors operate due to torque produced as the combined effect of magnetic field and electric current through a wire winding. Hence, We always need some means through which we can control the direction of the Motor to get the output that is suitable for our present requirement.

Performance of 2N2222 Transistor in H Bridge

The 2N2222 Transistor works as a backbone in the circuit of the H Bridge. We use four 2N2222 Transistors in the circuit and they work as a couple. The diagonal Transistors work together as a couple and allow the flow of current through them. By the same token, the non-diagonal 2N2222 Transistors work as a couple. Let's have a look at what is 2N2222 Transistor:

"The 2N2222 Transistor is a type of Bipolar Junction Transistors or BJTs that is designed to be used in the low power amplifying or switching applications."

DID YO KNOW???

Motorola made many semiconductor companies and the 2N2222 is  part of a huge family of Devices and Transistors that were discussed in IRE Conventions in Motorola company.

Being a BJT Transistor, the 2N2222 allows the flow of current in only one direction. Thus, it is responsible for the rotation of the Motor as per requirement of the user. The 2N2222 transistor (just as other JTs) has three pins. These pins are called Emitter, Base and Collector. The arrow symbol just at the transistor symbolizes the Emitter. Being an NPN Transistor, the collector and emitter terminals of 2N2222 Transistor in H Bridge act reverse biased or are said to be left open when the base pin is held to the ground or when there is no current flow from the base. On the other hand, when the base gets the flow of current from the battery or other components of the circuit in the H Bridge, the circuit is said to be forward-biased. The gain of the 2N2222 Transistor in the H Bridge ranges from 110 to 800. The value of gain is responsible for the determination of the 2N2222 Transistor's amplification capacity in the H Bridge.

Working of H Bridge Circuit

When we look at the circuit of H Bridge we get the following points:

1. The Direct Current from the battery originates from the positive terminal of the battery (considering the conventional current) and passes through the switch.

1. The switch allows the current to pass through the pair of the 2N2222 Transistor that is to be used.
2. The resistors just before the Transistors perform the regulation of the current through the transistors.
3. In our case, the H Bridge works according to the table given below:

Switch	Flow of Current	Direction of Motor
Connected to A	From T4 to Motor then Motor to T1	Anti-Clockwise
Connected to B	From T2 to Motor then Motor to T3	ClockWise

Let's have a look at the working of the H Bridge in action in Proteus ISIS.

Circuit of H Bridge in Proteus ISIS

We are going to design the circuit of the H Bridge in the Proteus ISIS. But before this, let's have a look at the required devices for the circuit.

Required Devices for H Bridge

1. 2N2222 Transistor
2. Resistor
3. Motor
4. Cell
5. Switch
6. Connecting Wires

Now,  just follow these simple steps:

• Start your Proteus Software.
• Click at the "P" button and choose the required devices except for connecting wires one by one.
• Arrange for 2N2222 Transistors, four Resistors, motor, switch and cell on the working area.
• Change the orientation of two of these Transistors before setting on the screen by clicking the arrow sign given just above the "P" button.
• Left Click the motor>Rotate clock-wise to change the direction of the motor according to the image given next:

• Change the value of Cell and Motor to 6v by double taping them one after the other.

• Connect all the components according to the circuit given next:

• Double click at all the resistors and transistors one after the other and label them to identify them as different devices.
• Pop the simulation button.
• Change the orientation of switch and check the output.

Task

Change the value of the transistors around the motor and observe the rotation speed of the motor.  

Truss today we saw, what is H Bridge, what is the role of 2N2222 Transistor in the circuit of H Bridge, How does the circuit of H Bridge works and we implemented the H Bridge circuit using 2N2222 Transistor in Proteus ISIS. Stay with us with more tutorials.

What is Velocity? Definition, SI Unit, Examples & Applications

Hello everyone! I hope this article will find you in great health. Today, in this article, we will discuss in detail: What is velocity? We will take a look at what exactly velocity is, how it can be measured, what scale has System International (SI) defined to measure the velocity, how many forms of velocity do exist in our surroundings, and what are the real-life applications of this physical quantity?

I will let you guys know about how velocity is a regular part of our daily lives and how it behaves in the environment we are living in. To understand the basic concept we need to have a deeper look at its real-life examples. A detailed discussion on velocity to have a better understanding is provided in the next section. Let’s get started.

What is Velocity?

An earthly object can possibly have two states i.e. rest or motion. If an object is in motion, a numerical value called Speed is used to measure how fast or slow the object is moving? Speed is defined as the distance covered per unit of time. So, if an object covers a distance of 1 meter in 1 second, its speed will be 1m/s. As speed is a scalar quantity so it just gives the scalar information(about motion) and doesn't tell us anything about the direction of the movement i.e. object is moving towards north, south or may have a circular motion.

So, in order to completely define the motion of an object, an equivalent vector quantity of speed was introduced and named Velocity. Velocity, not only gives the numerical value(speed) but also tells the direction of the moving object. In simple words, speed plus direction is equal to velocity and as speed is distance per unit time, similarly velocity is displacement per unit time.

Now let's have a look at a proper definition of Velocity:

Velocity Definition

• The velocity of an object is defined as the displacement(covered by it) per unit time in a particular direction.
• If two objects are moving in the same direction at different speeds OR in different directions at the same speed, they will have different velocities.
• Two objects will have the same velocities, only if both are moving in the same direction with the same speed.

Let's have a look at the symbol of velocity:

Velocity Symbol

• Symbols are used to represent physical quantities as writing the full name is time-consuming and sometimes overwhelming.
• The symbol used to represent Velocity is "v"(small character).
• As it's a vector quantity, so its symbol is either written in bold or with an arrowhead at the top.
• Sometimes, v(t) is also used as a velocity symbol, where t shows the time span.
• The below figure shows the velocity symbol more clearly:

Now let's have a look at the mathematical formula for calculating the velocity of an object:

Velocity Formula

• Velocity is defined as displacement per unit time, so its formula is:

Velocity = Displacement / Time

v = d/t

As v & d are both vector quantities, so written in bold while t is a scalar quantity.

• If we are calculating the average velocity of an object, the velocity formula will be:

Average Velocity = Distance Covered / Total Time

?v = ?d/?t

?v = (d2 - d1) / (t2 - t1)

where t1 & t2 are initial and final time intervals and d1 and d2 are initial and final displacements of the object.

Now, let's drive the velocity unit from its formula:

Velocity Unit (SI)

• As Velocity formula is:

Velocity = Displacement / Time

where SI unit of displacement is the meter and that of time in seconds.

• So, the SI unit of velocity is:

Velocity = meter / second

• SI unit of velocity is normally written as m/s or ms^-1.
• Other velocity units are:
  1. ft/s
  2. mph
  3. km/h etc.

In the game of cricket, the velocity of the ball is usually not measured in SI units rather they measure it in either kilometer per hour or miles per hour.

Velocity Dimensions

• Since the unit of displacement(meter) shows the quantity of length so its dimension would be “L”.
• Similarly, when it comes to the “second” it shows the amount of time so its dimension will be “T”.
• Putting these dimensions in the velocity formula, we have.

Velocity Dimension = [L/T]

v = [LT^-1]

 

Few Velocity Terms

Depending upon various factors, velocity has been divided into multiple types as discussed below. Let’s read through them all.

Negative Velocity

• If an object is moving in a coordinated plane, then its velocity is measured from some fixed reference point.
• In such cases, if the object is moving away from the reference point, its velocity is termed as Negative Velocity.

Let's understand it with an example of a ball thrown upwards:

As we know, Earth's gravitational force pulls everything towards it. So, considering the earth as a reference point, when you throw a ball in the upward direction, it's moving away from its reference point(Earth's center). So, during its upward flight, the ball will have a negative velocity and thus is written with a negative sign.

Zero Velocity

• When an object is not covering any distance with respect to the varying time, it will be said to have Zero Velocity.

Let's continue that example of the ball moving upward:

As we have seen in the previous section, the ball will have a negative velocity while moving upward. But when it will reach the maximum height and rite before moving back in the downward direction, for an instance it will have a zero velocity, as it won't be moving either upward or downward.

Positive Velocity

• If the object is moving towards the reference point of its coordinate system, its velocity is termed as Positive Velocity.

Let's add some more in that ball example:

Once the ball reaches the maximum height, it will start moving back in the downward direction. Now, the ball is moving towards its reference point(Earth's Core) so it will be said to have positive velocity now.

Initial Velocity

• As moving objects have variable velocities over different periods of time, that's why velocity is normally measured in the rate of change(?v).
• So, the first velocity of the object, when it comes under observation is termed as Initial Velocity.
• The Initial Velocity is also termed as the velocity of an object at time t = 0.
• Initial velocity is denoted in Physics by the alphabetic letter "u" or "Vi".

Let's understand it with the same example:

We have seen the ball example thrown upward. If we consider both of its loops(moving upward and then downward), its initial velocity will be right where it left the hand of the thrower. It will have a maximum initial velocity as during the upward direction it will slow down and during the downward direction, it will lose some to friction. But if we only consider the second loop i.e. the ball has reached its maximum position and now it's moving downwards. So, in this scenario, the initial velocity of the ball will be 0. I hope it got cleared.

Initial Velocity Formulas:

• Using the equation of motion, we can easily derive different mathematical expressions for the initial velocity. The first equation of motion is,

v = u + at

• If we are provided with the time, final velocity, and acceleration, we can calculate the initial velocity using the formula given below.

u = v - at

The above expression shows when we multiply acceleration with the given time and subtract this product from the final velocity, it gives us the initial velocity.

• If a scenario comes where distance, final velocity, and acceleration are provided, we can find initial velocity from a mathematical expression given below:

u² = v² - 2aS

• In case, we have only time, distance and acceleration to find out the initial velocity, we can use the formula shown below.

u = S/t - (1/2) at

• If the final velocity, time, and distance are provided in the statement, an effective way to find out the initial velocity is given below.

u = 2(S/t) - v

 

where,

• u = initial velocity.
• v = final velocity.
• a = acceleration.
• t = time consumed.
• S = distance covered.

Final Velocity

• The velocity of a body at the end of the provided time is known as the Final Velocity.
• We can also define Final Velocity as the last velocity of the object while it's under consideration.
• The final velocity is usually denoted by “v” or “V_f”.

Final Velocity Formulas

• Using the equation of motion, the final velocity can be easily calculated with the formula given below, when we are provided with the initial velocity, acceleration, and time consumed:

v = u + at

or

V_f = V_i + at

• If the statement has asked us to calculate the final velocity and provided us with distance, initial velocity, and acceleration. We can use the below formula for quick calculations.

V_f² = V_i² + 2aS

Where,

• V_f = Final Velocity.
• V_i = Initial Velocity.
• S = Distance covered.

Let's understand the concept associated with the final velocity through a visual example.

A projectile motion of the ball thrown from one end is shown in the figure below. At time zero (t = 0), when a guy in a purple shirt throws a ball, the velocity of that ball at this time is considered initial velocity. After reaching a particular height, when the ball starts moving downwards and reaches at t = 8 seconds in the hands of a guy wearing a green shirt. At t = 8 seconds, the velocity of the ball is the final velocity. After this velocity, an object comes again into the stationary position.

Similarly, if you drop a ball from a specific height and allow it to move towards the ground as shown in the figure below. The moment you drop the ball, the velocity is called initial velocity. Whereas, the moment when the ball touches the ground, the velocity will be known as the final velocity.

Now let's have a look at different types of velocity in detail:

Types of Velocity

Depending on the type of object and its motion, we have numerous types of velocities, a few of them as discussed as follows:

Average Velocity

• When an object is moving in a specific direction, the ratio between the total displacement covered and total time consumed is known as the average velocity of that particular body in motion.
• It is denoted by “v” or "Vav".
• We can also define this quantity as the average rate at which the body changes its position from one point to another point.

Average velocity = total displacement covered / total time taken

• If we take the difference between the initial and final displacements and divide it by the difference of initial and final time, it will give us average velocity in return.

?v=?x/?t

?v = (x2-x1) / (t2-t1)

Where,

• x2=final displacement
• x1=initial displacement
• t2=final time
• t1=initial time

Average velocity cannot tell us how fast or slow an object is moving in a specific interval of time and for that, we have another type of velocity called Instantaneous velocity.

Instantaneous Velocity

• The velocity of an object at a particular instant is known as the instantaneous velocity of that object.
• In other words, the velocity of a moving body at a specific point is its instantaneous velocity at that point.
• Instantaneous velocity is similar to average velocity but we need to narrow the time intervals i.e. time approaches to 0.
• It is denoted by “Vinst”.
• If any subject has a fixed velocity over a specific time period then its instantaneous and average velocity will be the same.

By applying a limit “t” approaches zero on the average velocity provides us with the instantaneous velocity as shown in the formula given below.

V_inst = Lim _{t -> 0} (?d/?t)

Take a look at the figure below, the velocity at point “p” depicts the instantaneous velocity of a moving body.

The figure below shows the relation between average and instantaneous velocity. The velocity is represented by the red line and has been divided into several segments. The position is displayed on the y-axis whereas the x-axis shows the time consumed. In the first interval, Jack has covered 3 miles in the first 6 minutes. In the second interval, Jack stopped for 9 minutes. Whereas, in the third interval, Jack covered another 5 miles in 15 minutes. If we divide the total displacement covered by Jack by the total time consumed during the whole travel, it will give us an average velocity.

Constant Velocity

• If a body is traveling at the same speed for a long time and is not changing direction, then its velocity will be considered as Constant Velocity for that particular interval of time.
• In other words, it can be said that a body will have a constant velocity if it is moving at a constant speed along the straight line. This straight line can be represented by the formula given below.

x=xo+vt

Where,

xo=position of the body at t=0

• An object can have a constant velocity if it is moving in the presence of very little or no friction. Less friction allows that object to move freely just like in ice hockey where a hockey puck slides on the ice as shown in the figure below.
• If an object is moving with a constant velocity, it will have zero acceleration because acceleration is the rate of change of velocity per unit time.

a=dv/dt=0 v=constant

This scenario can be visualized through a velocity-time graph as shown in the figure below. You can see a straight line for each time interval depicting the velocity is constant throughout with “0” acceleration.

Variable Velocity

• If the velocity of an object is changing in either direction or magnitude or both, it is said to have a Variable Velocity.
• If an object is in a motion and is covering unequal distances for every equal interval of time, we can say it is moving with a variable velocity.
• In simple words, variable velocity is a type of velocity that changes with time.

Let's understand this from a real-life example.

For instance, if a fan installed in your room is rotating at a continuous speed, its velocity will be variable because its direction gets changed every time.

Orbital Velocity

• The velocity required to make an object overcome its gravitational force and rotate within an orbit is called orbital velocity.
• The movement of satellites around the earth and the movement of stars around the sun are the best examples of orbital velocity.
• It is denoted by “Vorbit” and for Earth, its mathematical formula is:

Vorbit=GMR

Where,

• G=gravitational constant=6.6710-11m3kg-1s-2
• M= mass of the planet
• R=radius

Escape Velocity

• Escape velocity is the type of minimum velocity required for an object to escape from the gravitational force of a massive body (moon, earth, etc.) and to move out somewhere in space.
• Escape velocity increases with an increase in the mass of a body.
• It is denoted by “ve” and depends upon various parameters including the mass of the planet and radius.
• We can calculate it using the mathematical expression given below.

ve=2GMr

Where,

• G=gravitational constant.
• M=mass of the planet.
• r=radius.

Angular Velocity

• The rate of velocity at which a body rotates around a particular point or center in a given amount of time is called angular velocity.
• It can also be defined as the angular speed at which a body rotates along a specific direction.
• Angular velocity is denoted by omega “?”.

Angular Velocity Unit

• System International has assigned this quantity with a unit known as radians per second.
• This quantity can also be measured in many other units as well depending on the requirements and they include:
  1. degrees per second
  2. degrees per hour

Let's have a look at how to find the angular velocity of a moving object?

Angular Velocity Formula

To calculate this quantity, a formula is given below.

?=??/?t

Or,

?=v/r

Where,

• v=linear velocity
• r=radius
• ?=angular velocity

Conversion of Angular Velocity into Rotational Velocity

• When we measure angular velocity in either revolution per minute or rotations per unit time, it becomes rotational velocity.

The direction of motion of an object moving with angular velocity is always perpendicular to a plane of rotation. It can be measured using the right-hand rule. The whole concept is shown in the figure below.

 

Linear Velocity

• As it is very clear from the name of this quantity, when an object moves along a straight line in a single direction, its velocity will be a linear velocity.
• It is simply denoted by the alphabetic letter “v”.

The above figure shows that the linear velocity is dependent on the two different parameters i.e., distance covered and the time consumed to cover that particular distance.

Let's have a look at how to find linear velocity?

Linear Velocity Formula

It can be calculated using the below mathematical expression.

velocity=distance/time

v=S/t

As we know,

S=r?

Putting this value in the above formula we have,

v=r?/t

The linear velocity can also be represented in terms of an angular velocity as given below.

v=r?

Terminal Velocity

• A steady speed that an object achieves when falling through the liquid or gas is known as its terminal velocity.
• In other words, we can describe this quantity as the constant vertical velocity of an object.
• It can also be defined as the highest velocity maintained by a body that is falling through the liquid
• It is denoted in Physics by “vt”.

Factors Involved in Terminal Velocity

• This quantity is dependent on multiple factors e.g.,
  1. the mass of the object
  2. drag coefficient, acceleration
  3. projected area
  4. fluid density.

Terminal Velocity Formula

• Terminal velocity can be calculated using a mathematical expression given below:

vt=2mgACd

Where,

• vt=terminal velocity
• g=gravitational acceleration=9.8 ms-2
• m=falling object's mass
• Cd=drag coefficient
• A=projected area
• ?=fluid density

Uniform Velocity

• A scenario when a moving body is covering the equal displacement in equal internal in a fixed direction is said to have a uniform velocity.
• It is a stable velocity that does not change in multiple intervals of the time consumed and direction remains the same too.

Let's understand with an example.

• A motorbike traveling with a speed of 20 kilometers per hour towards the east has uniform velocity.
• Uniform velocity can be easily visualized on the distance-time graph as shown in the figure below.

Non Uniform Velocity

• A body that covers unequal displacement in equal time intervals is said to have non-uniform velocity.
• In this case, either direction of motion or both rate of motion and direction can be changed for an object in motion.

Let's understand this with a visual example.

The track of a car moving with non-uniform velocity is shown in the below figure. Unequal displacements covered in equal intervals of time can clearly be seen from the velocity-time graph.

Relative Velocity

• Relative velocity is the vector difference between the velocities of two different objects.
• It can also be defined as the velocity of an object with respect to an observer who is at rest.

Let's understand the overall scenario with an example.

For instance, the air is causing some hindrance in the airplane’s track or a boat is traveling through the river whose water is flowing at a particular rate. In such cases, to observe the complete motion of the object, we need to consider the effect of the medium affecting the motion of a moving body. By doing so, we measure the relative velocity of that moving object as well as the medium’s velocity affecting its motion

Let's have a look at another example to have a better understanding of relative velocity.

Finding Relative Velocity

• The relative velocity of an object “x” relative to the object “y” can be expressed as shown below.

Vxy=Vx-Vy

• Similarly, the relative velocity of an object “y” relative to the object “x” is given below.

Vyx=Vy-Vx

• Taking a look at the above equations, we can develop it as:

Vxy=-Vyx

• The above equation shows that both relative velocities are equal in magnitude but opposite in direction.

|Vxy|=|Vyx|

• In the first case, the observer is moving in the rightwards and the ball was thrown by a girl is moving in the same direction and the person dragging that girl is traveling in the same direction as well. Therefore, all these quantities are positive.
• In the second case, the girl is throwing the ball in opposite direction to the direction in which the observer is moving. That is why the signs of the velocities are negative for both the observer as well as the ball.

Now, let's have a look at what parameters creates a difference between speed and velocity.

Difference Between Velocity and Speed

It has been proved through various research studies that most of the time people get confused when it comes to speed and velocity. They mostly get confused in implementing their concepts separately in different scenarios as and when needed.

Basic Difference

If I tell you the very basic difference between these two quantities, they are just as different as distance and displacements are.

• Speed is the rate of change of distance with respect to the time consumed in covering that particular distance.
• Whereas, velocity is the rate of change of displacement (shortest distance) covered by a moving object in a specific direction per unit of time.

Let's have a look at some more points to understand the difference effectively.

• Speed depicts that how fast an object has the ability to move. An object at a stationary position always has zero speed. The speed needs no direction to be defined.
• It is a necessity for someone to consider the direction in which a body is moving if one is going to describe the velocity.

Therefore, keeping in mind the above points, it can be said that a direction creates a major difference between speed and velocity.

• The quantity that doesn’t require direction to be measured is known as the scalar quantity and it only needs magnitude to be defined. Therefore, speed falls into the category of scalar quantities.
• The quantities that need direction and cannot be defined without it are known as the vector quantities. Therefore, velocity belongs to the family of vector quantities.

Let's understand through an example.

For instance, 30 kilometers per hour is the speed of a moving vehicle whereas 30 kilometers per hour east shows the velocity of the same vehicle.

• It is very simple to calculate the speed of any moving object compared to calculating the velocity of the same object.
• Average speed is the ratio between distance traveled and the time taken.
• Whereas, the average velocity is the ratio between the change in position (?S) and the change in time (?t) consumed.

Findings

• In the light of the above discussion, we can say that the speed with the direction forms a velocity.
• In order to provide a much better understanding of speed and velocity and their basic differences are listed in the table shown below.

Parameters	Speed	Velocity
Definition	The rate at which a body covers a particular distance is commonly known as speed.	The rate at which a body changes its position in a specific direction is called velocity.
Magnitude	Speed is always positive and it cannot be either negative or zero.	Velocity can be positive, zero, and negative depending upon the direction in which an object is moving.
Quantity Type	Speed does not need any direction for its description so, it is a scalar quantity.	Velocity cannot be described without direction so it is a vector quantity.
Change in Direction	Change in direction does not matter when calculating average speed.	Every change in direction changes the velocity.
Formula	s=distancetime=dt	s=change in positionchange in time=st
SI Units	Meter per second (m/s)	Meter per second (m/s)

Examples of Velocity

A few examples of velocity from real-life are presented to clear your concepts related to it if there still exists any confusion.

• Suppose, you go to your school to maintain your studies on a daily basis. The school is situated to the west of your home. Here, you can observe that you always go towards the west from the starting point which means you go in a particular direction that depicts velocity. Your speed could be high or low.
• In the game of cricket, when a ball is thrown by the baller towards a batsman is also a great example of velocity from our daily life because it follows a single direction.
• The way the moon revolves around the earth and the earth moves around the sun is another example of velocity from nature because of its single direction.
• The ceiling fan rotating in your home during summers also belongs to the family of velocity due to its either clockwise or anti-clockwise rotation.
• The movement of the train from one city to another also follows a specific track in a single direction.
• A revolution of a launched satellite around the earth.
• Water coming from the tap when you open it.
• The flow of the river (it depicts variable velocity).
• Anyone doing morning walk or running.

Final Words

This is all from today’s article. I have tried my level best to explain to you each and everything associated with the velocity. I have focused in detail on its basic concept, various forms, unit assigned by System International, and visual examples where needed. Moreover, I have provided you with a couple of examples captured from real life so that you can have a better understanding of velocity.

I hope you have enjoyed the content and are well aware of this topic now. If you are looking for more similar information, stay tuned because I have a lot more to share with you guys in the upcoming days. In case you have any concerns, you can ask me in the comments. I will surely try to help you out as much as I can. For now, I am signing off. Take good care of yourself and stay blessed always.

Thank You!

Real estate management: The Need for Routine Repair and Maintenance

As an investor or manager in the real estate industry, it is imperative to care for the property. Whether you are leasing or living on the property, it is essential to be proactive in repair and maintenance. Lack of routine inspection can lead to unprecedented expenses for landlords and homeowners. Read on to find out ways to prevent system failures and increase their service life, in turn.

It is an Extensive Activity

For proper care and maintenance of real estate, it is critical to understand the property. However, it would be best if you had qualified personnel take a look at the place to give a professional opinion. There are different types of MRO (maintenance, repair, and operations) to improve real estate management. Businesses need to keep up with the industry trends to know what a CMMS is and ways it can improve business processes. It does not matter what industry the venture operates in. The systems can be customized to fit your business needs.

Being proactive in the approach entails engaging in both preventive and continuous maintenance. Here are tips that can help real estate managers and homeowners increase the property’s service life;

Conduct a Home Inspection

Regular inspection of the systems in real estate can help identify a problem before disaster strikes. The harsh weather conditions play a significant role in the need for routine repair and maintenance. Whenever the season changes, have a home inspection to determine the damage. It will also help in planning for the next season and acting accordingly. However, without inspecting the systems, you will discover the problem when the damage is already done. It is also costly to replace a whole system in a building than to repair minor issues as it is detected.

Preventive Maintenance Techniques

For you to protect the property from degradation, it is critical to engage in preventive maintenance activities. It is beneficial when real estate managers and homeowners undertake the initiative of preventing severe damage to building systems.

Some of the best practices in real estate management are;

HVAC System care

Purchasing an HVAC system is costly. Replacing the components is expensive as it might require you to order the parts. However, we can prevent some of the challenges through routine repair and maintenance. The practice will also ensure the system is performing as per the manufacturer’s specifications. You will be using the system across all seasons, and it is critical to make the care more frequent. The malfunction of such equipment will depend on the amount of time they are in operation. 

Environmental Management

Trees suffer when snow accumulates on them. The parts become weak and will fall off if there is no action taken. On the other hand, there is a risk to the property when the trees fall as it may cause damage. So, it is critical to maintain the environment and identify any risks that nature poses to the property.

Proofing Leakages

One of the most undetectable problems always waiting to explode in modern buildings is leakages on the roofing system. It is essential to clean the gutters to ensure water is flowing through the roofing system. If the roof is susceptible to water, it is important to consider changing the whole system and use a material that prevents water from leaking.

When water gets into the roof, molds will likely start to form. On the other hand, water may damage the ceiling and may make it fall. Proofing for leakages will prevent the eventualities. The inspection activity can help detect impending challenges on the roofing system and prompt immediate action.

Manage the Repair and Maintenance Expenses

When purchasing property, the initial cost is known as capital investment. However, it is essential to monitor the subsequent costs arising from repair and maintenance needs. Ensure to record all the expenses either on paper or on a computer. 

Follow the insights in this read to manage a real estate property better.

12V to 220V Step Up Inverter using transformer in Proteus

Hey learners! Welcome to another exciting electrical experiment in Proteus. At the present day, we'll perform the inversion of voltage. For this purpose, we will use the implementation of Transformer as Step-up Transformer. Prior to start, let's have the basic information about the 12V to 220V Step up inverter using Transformer in Proteus. In this tutorial, we'll learn:

1. What is a 12V to 220V inverter?
2. What is the function of the transformer in the 12V to 220V inverter?
3. How can we implement the Step up inverter using a Transformer in Proteus?
4. What are some applications of the 12V to 220V inverter?

Moreover, there will be some useful pieces of information in DID YOU KNOW sections.;

12V to 220V inverter

In electronic appliances, the circuitry is designed so, that the appliance can work in a specific range of Voltage, Frequency and power etc. If these quantities are not supplied using these parameters, then the Appliance does not work ideally. For example, if the given voltage to a bulb is less than its voltage range it may be lightened dim. or if the voltage is given more than the range of the bulb, the circuitry of the bulb may be damaged or even it may burst. In such a case, the invertors are used that inverts the voltage (or other electrical quantities according to type) into the suitable range is used. Therefore, the 12V to 220V inverter can be defined as:

"An invertor is the electrical circuit that converts the 12V Direct current into 220V Alternating current and alters supplied voltage range into required range."

By using the 12V to 220V inverter the electrical or electronic circuits, we can use the electrical circuits that work on the 220V even when the supply from the source is 12V.

DID YOU KNOW??????????????

"The Inverters play a life saving role in the appliances that have a sensitive circuit to voltage and current. Even the High voltage more than the range of the device can burn the circuit so badly that it may require to change the whole circuitry or the motherboard of the device."

 

Working of 12V to 220V invertor

in the process of 12V to 220V inversion, three major process takes place:

1. Supply
2. Conversion
3. Transformation

We use simple circuitry to perform each task. Based upon the functionality, we use three devices in the circuit of 12V to 220V inverter. These are:

1. Battery
2. Transistor
3. Transformer

Role of Battery in 12V to 220V Transformer

It is obvious that every circuit requires some sort of energy to perform the required function. In 12V to 220V Inverter, we use a 12V battery that will be supplied to whole components. The 12V battery performs the "Supply" process in the 12V to 220V Inverter.

Role of Transistor in 12V to 220V Inverter

The process of conversion of direct current into alternating current requires a mechanism that allows just the positive side of the sinusoidal wave of the Alternating current to pass through it and hence one can get only one side of the output wave of current. In the case of low and medium applications, power Transistors are used. The reason behind this logic is, the Transistors:

• are Less in cost.
• have low output Impedance.
• Allow most of the power to pass through it.

We know that the Transistor work as a switch. the two type regions of the characteristic graph of the Transistor are used in this experiment. Saturation region: In this region the transistor is biased. The collector-Emitter and the Collector-base junctions are forward biased. The collector has the minimum voltage and the collector current is maximum. Cut-off Region: In this region, the Transistor does not allow the current to pass through it.

Role of Transformer in 12V to 220V Inverter

The Transformer is the mechanical device used o transform the voltages from its input to its output. It has two sides that have coils around them. In our experiment, we use the Step-up Transformer that is introduced as:

"The type of Transformer that is used to convert the low voltage and high current supplied to its input to the high voltage and low current at its output is called the step up Transformer."

Hence the voltage from the Transistor that is rectified and has the direction only on one side is fed at its input. The Transformer transforms the low voltage into the high voltage. In this way, we get a high voltage. The ability of the transform to amplify the voltage depends upon the number of turns of the coil on its terminals.

DID YOU KNOW???

"If you get a transformer that have the same mechanical structure but it has the numbers of turns in primary coil grater than the secondary coil then it is called the step down Transformer. "

Implementation of 12V to 220V inverter using Transformer

At the present moment, we'll use all our concepts given above to design the circuit for the 12V to 220V Inverter. Just follow the simple steps given next.

• Power up your Proteus circuit.
• Choose the material given below.

Material Required

1. 3WATT68R (This resistor works at the 68R resistance automatically.)
2. Battery
3. Lamp
4. MJ-2925
5. Trans-2P3S (Step-up Transformer)

• Click at the components one after the other and arrange the components one after the other at the working area.
• Left-click at the Battery and choose "Rotate 180 degree".
• The screen should look like this:

• Change the values of some of the components by following the table given next:

Devices	Values
Battery	12V
Bulb	240V
Bulb Resistance	100k
Transformer Primary Inductance	100H
Transformer Total Secondary Inductance	1.1H

 

• Connect the elements with the help of the diagram given below:

• Simulate the circuit by clicking at "Play" button given on the lower-left corner of the screen.

You will observe that the bulb is light although it is set as a 220V device and the supplied voltage is just 12V.

Applications of 12V to 220V Inverter using Transformer

1. To charge the small batteries of vehicles such as cars.
2. Low power Alternating Current Motors.
3. Solar Power system.
4. Uninterrupted Power Supplies (UPS).
5. Reaction power controllers.
6. Adapted power Filters.

Adjustable speed Alternating Current Motor Drivers. Consequently, we saw about an electrical circuit today that converts the 12V from its input to 220V at its output using the Transformer. This experiment has many interesting applications. Stay with us for more experiments.

Pulse Width Modulation using 555 Timer in Proteus

Hello Engineers! Welcome to the board. We hope you are having a good day. In this tutorial, we teach you about Pulse Width Modulation. We'll discuss some important points about the topic. Let's have a look at the Topics of the tutorial:

1. What is Pulse Width Modulation?
2. What is 555 Timer?
3. how does 555 Timer is used in the Pulse Width modulation circuit?
4. How do we design the circuit of Pulse Width Modulation in Proteus ISIS?

In addition, you will have some useful information bout Pulse Width Modulator in DID YOU KNOW section.

Where To Buy?
No.	Components	Distributor	Link To Buy
1	555 Timer	Amazon	Buy Now
2	LEDs	Amazon	Buy Now
3	Resistor	Amazon	Buy Now

Pulse Width Modulation

Pulse width Modulation is a useful technique in the world of Modern Electronics. Let's have a look at the information about Pulse Width Modulation.

Abbreviation of Pulse Width Modulation

The Abbreviation of the Pulse Width Modulation technique is PWM.

Definition of Pulse Width Modulation

We define the pulse Width Modulation as:

"The Pulse Width Modulation is the technique  in the electronics to control the power given to the analogue devices through which the average power delivered by the electrical signal is reduced due to division of the signals into discrete parts."

The Pulse Width Modulation is important to the inertial load devices such as motors because in these devices the change is slow due to their inertial ability and the Pulse Width Modulator has enough time to control the device.

Example of PWM

We know that in the bulb that we use in our daily life, the AC Power changes its direction from positive to negative cycle and vise versa. The frequency through which the cycle change decides the brightness of the bulb. Consider the example of the circuit in which the LED is connected to the power. The Power connection lightens the LED. When the switch between the power source and the bulb is close, the power is transmitted to the bulb and the brightness is observed. The opening and the closing of the switch can be controlled through the Pulse Width Modulation. The more is the duty cycle of the Pulse width, the more rapidly it opens and closes the switch and hence the brightness of the bulb is more and vise versa. hence we can conclude that by controlling the pulse width we are controlling the opening and closing of the switch and through which we are controlling the brightness of the bulb.  

DID YOU KNOW????????????

"The Pulse Width Modulation technique is also called as the Pulse Duration Modulation or PDM. It is because this technique works with the duration of the cycle of the circuit. "

555 Timer in Pulse Width Modulation

Prior to start the work of 555 Timer in Pulse Width Modulator, we must clear some important concepts about the 555 Timer device. Let's have a glance on the points.

Definition of 555 Timer

The 555 Timer was termed as the SE NE555 Timers. Another Type of the 555 Timer is SE555 Timer. These were first invented by "Signetic Corporation" . We define the 555 Timer as:

"The 555 Timer is an 8 pin Integrated Circuit that generates accurate timing pulse. The designing of the 555 timer is done by collectively arranging the electrical and electronic components such as resistors, transistors, diodes and Flip Flops."

These are monolithic Timing circuits that are designed to provide stable time delay and oscillations. These are highly reliable and low in cost.

Pin out of 555 Timer

There are 8 pins of 555 Timer and each pin has its own function and operation. For the best concept, we have designed a table for each pin given below:

Pin Number	Pin Name	Description
1	Ground	This pin is labeled as GND and used to supply the 0 voltage.
2	Trigger	When the Time interval starts, the output remains low when this pin is high and vise versa.
3	Output	This is the output pin.
4	Reset	This pin overrides the Trigger pin and that overrides the Threshold. It is connected with Vcc if not used.
5	Control	It controls the Pulse Width and the level of threshold and Trigger.
6	Threshold	Hen the voltage is applied at this pin, it acts in the contrast to the voltage.
7	Discharge	This pin is an open-collector output. During the intervals, this pin is used to discharge the capacitor.
8	Supply	This is the power supply pin. The input of power is taken against the Ground pin.

DID YOU KNWO???????????

"We use the counter instrument in the Proteus to count the Pulse Width Modulation of the circuit using 555 Timer."

Implementation of PWM using 555 Timer in Proteus ISIS

To implement the Pulse Width Modulation using 555 Timer, we are using the simulation in Proteus ISIS. To Implement the 555 Timer PWM  just follow the simple steps given next:

• Fire up your Proteus Software.
• Choose the following components:

1. 555 Timer
2. 1N4148 Diode
3. 3005P-1-502 Variable Resistor
4. DC Power Supply
5. Resistor
6. Counter
7. Oscilloscope

• Fix first five components from the "Pick Library" at the working area.
• Change the values of Resistor, Capacitors and variable Resistors according to the table given below:

  Component	Values
  Resistor	1k ohm
  Variable Resistor	50k ohm
  Capacitor 1	10nf
  Capacitor?	1uF
  DC Power source	10V

   

• Go to Terminal mode>Ground and set it at the end of the circuit.
• Connect the components through the connecting wires according to the image given next:

• To get the counting of the output, go to virtual Instrument Mode and choose the counter.
• Go to Virtual instrument Mode and select the Oscilloscope.
• Connect the counter with any terminal of the Oscilloscope.
• Join both the instruments with pin 3 of 555 Timer.

• Pop the play button and simulate the circuit.
• Change the values of voltages and the frequency according to need.
• We observe that the Oscilloscope shows us the width as:

Thus, Today we saw what is the pule Width Modulation, learned some important concepts about the 555 Timer, got some important concepts about Pulse Width Modulation using the 555 Timer and saw the simulation by the mean of Proteus ISIS. If you found it useful, give us your important feedback in the comment section.

Metal Detector using 555 Timer in Proteus

Hello Pupils! I welcome you to the board. I hope you are fine. In today's tutorial, we will design a project Metal Detector using 555 Timer in Proteus ISIS. All of us perceive the situations when at the public places such as on airports or in shopping malls where sharp metallic objects such as a knife or illegal guns or even a nail cutter are not allowed, there are walkthrough gates at every entrance so that any person with the forbidden material when passes through the gate, the alarming buzzer automatically switched on. This happened because the walkthrough gates have the Metal Detector circuit in them that works immediately when such a situation occurs. In this session, we'll learn:

1. What are Metal Detectors?
2. How does the 555 Timer collaborate with the circuit of Metal Detector?
3. How does the circuit of the 555 Timer Metal Detector works?
4. How can we implement the circuit of 555 Timer Metal Detector in Proteus?

In addition, you will also have some useful pieces of information in DID YOU KNOW Sections.

Where To Buy?
No.	Components	Distributor	Link To Buy
1	555 Timer	Amazon	Buy Now
2	LEDs	Amazon	Buy Now
3	Resistor	Amazon	Buy Now

NE555 Timer Metal Detectors

Metal Detectors became the one of the necessary devices for many public Places either it is park or bank, airport or any supermarket. It is because they play a vital role in the maintenance of security. Most of the metal detectors We define the Metal Detector as:

"The Metal detectors are the specialized NE555 Timer gadgets that detect the presence of the metals when the metals enters in the range of Metal Detector Circuits."

The NE555 Timer Metal Detectors does not only have the application i the field of security but they are also used in a variety of situations. The NE555 Timer Metal Detector can be categorized into three basic Families:

1. Very Low Frequency Detectors.
2. Pulse Induction Detectors.
3. Metal Detectors for specific Purpose.

DID YOU KNOW??????????????????????

"1960 was the year in which the 1st Metal Detector was established using simple devices in industrial and Mineral Prospecting. "

There are many kinds of NE555 Timer Metal Detectors that are used for different operations some of them are listed below:

1. Diagnostic Purposes.
2. Detecting myriad of foreign objects.
3. Finding the presence of bullets.
4. Detecting the intraocular metallic fragments.
5. Finding Swallowed coins.

Working of NE555 Timer Metal Detector

When we talk about the working of the NE555 Timer Metal Detector, we must have a clear idea about the following concepts:

1. Inductance
2. NE555 Timer operational system

Inductance in NE555 Timer Metal Detector

Let's recall the idea of Inductance that we are learning from our physics class:

"The Inductance, in electromagnetism and electronics, is the ability of a conductor of electricity to negate the change in the electric current that is flowing through it. This flow of electric current produces a magnetic field around that electrical conductor."

In the NE555 Timer Metal Detector circuit, we use an inductor that senses the presence of the Metal near to it. More close a Metal Detector to it, the more electric field lines are produced and hence the speaker gives the sound more loudly indicating the distance between the NE555 Timer Metal Detector and the metal's distance. We denote the Inductance through "L". Hence the formula to find the Inductance through any Conductor can be find through: Inductance= Magnetic Flux of Current/Current.

DID YOU KNOW ???

"There are some Metal Detectors that are used to find the treasure or ancient metals underground. They are so powerful that they can detect the Metal many feet away.  Thus, many people have a life changing search due to these useful instruments."

NE555 Timer

NE555 Timers belongs to the Family of 555 Timers Integrated Circuits. These are highly utilitarian circuits that are considered as one of the most used Integrated Circuits in the world of Electronics. We introduce the NE555 Timer as:

"NE555 Timer Circuit is the widely used Integrated Circuit having 8 pins and used to have the output that have a uniform pulses that can be set according to need."

The 555 Timers are used to have a variety of pulses that depends upon the arrangement of the devices connected to their Pins. There are three kinds of NE555 Timer modes:

1. Monostable Mode.
2. Astable Mode.
3. Bistable Mode.

Operations in the NE555 Timer Metal Detector Circuit

• When we examine the Circuit of NE555 Timer Metal Detector, we find these operations:
• The power of all the components is the Direct current that is provided by the battery.
• This power enters the NE555 Timer circuit that produces the uniform Timer-based Pulse at its output pin.
• This Pulse enters the resistor that controls the flow of current through the main Metal Detector circuit.
• The Resistor passes this current to the Inductor. The Inductance of the inductor is the basic criteria of distance measurement.
• As in Proteus, it is not possible to show the Movement of a Metal, so the value of the inductance represents the number of electric field lines around the NE555 Timer Metal Detector circuit. More is the Inductance, more numbers of lines passing through the inductor and hence it is assumed that metal is more near to the circuit. 
• The DC current then passes through the speaker according to the strength of the electric field lines and hence we found the faint or hard sound.

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Circuit design of 555 Timer Metal Detector in Proteus

• Power up your Proteus Software.
• Choose the following components from the Pick Library button "P".

Components Required

1. NE555 Timer
2. Inductor
3. Capacitor
4. Resistor
5. Speaker

• Take all the Components from the left section and arrange all of them on working screen according to the diagram given below:

 

• Now, Change the values of some of the components one after the other by double clicking the components.
• Inductor= 150mH, Capacitor 1=2.2uF,Capacitor 2=2.2uF,Capacitor 3 10uF, Resistor= 47k Ohm, Battery=9V.
•  Connect the circuit components with the help of connecting wire so our circuit look like this:

• As soon as the Circuit is simulated by hitting the Play button, the user sense a sound or buzzer from the circuit.
• If you heard it then cool, otherwise look at your circuit once again.

Task

Change the value of inductor to 300micro Farad and more to hear the louder sound.

Hence today, we saw what are NE555 Timer Metal Detector, How do they are classified, how does the circuit of 555 Metal detector works and how can we design its circuit using simple devices in Proteus ISIS. Stay with us for more projects.

Police Siren Project using 555 Timer in Proteus

Hey Geeks! Welcome to The Engineering Projects. We hope you are having a reproductive day. We know that sirens are the special sounds that are the symbol that something unusual is occurring or about to occur. You may have experienced the Siren of the Walkthrough Gates at the airport when a person having the knife or other forbidden material pass through it. Or you have heard the Siren of the ambulance and seen that all the traffic gives the way to the ambulance when they hear the special Siren of the Ambulance. The same is the case with the police Siren. The Police sirens are the special sound and it is set with the help of 555 Timer Integrated Circuit. You will learn how can one design a Police siren using the 555 Timer circuit in this tutorial. Let's have a quick list of the topics that will be clear in our tutorial.

1. What is the 555 Timer Police Siren?
2. What are the 555 Timer and its modes?
3. How does the circuit of 555 Timer police Timer Circuit works?
4. How can you design the circuit of 555 Timer Police Siren in Proteus?

Where To Buy?
No.	Components	Distributor	Link To Buy
1	555 Timer	Amazon	Buy Now
2	LEDs	Amazon	Buy Now
3	Resistor	Amazon	Buy Now

555 Timer Police Siren

The Police Siren we have seen many times in real life as well as in Television shows and Movies are made of the special arrangement of the 555 Timer. The Siren has a loud voice that can be heard at a distance of many feet. This Project has a very simple yet amazing arrangement of some basic electronic devices. The heart of Police Siren is the 555 Timer integrated circuit. In the police siren, two 555 timers are used. This is a Multi-functional chip that is widely used in different types of the industrial as well as household applications. If we look at the configuration of 555 Timer Integrated Circuit then we can generate a table just as shown next:

Pin Number	Attachments
1	Ground
2	Trigger
3	Output
4	Reset
5	Control
6	Threshold
7	Discharge
8	Vcc

Technically, The 555 Timer works in 3 modes:

• Monostable Mode
• Astable Mode
• Multistable Mode

Monostable Multivibrator Mode in 555 Timer

This mode of the 555 Timer contains a single stable state that can be used to get only one single output pulse of a specific width that may be high or low by applying an external trigger pulse. In this circuit, the 555 Timer uses only one resistor but two capacitors.

Astable Mode in 555 Timer

As the name shows, the Astable mode does not have any stable state. The Astable mode of 555 Timer has 2 quasi-steady states that change from one state to another one after the other. In this way, the 555 Timer in this state, alters the output from high to low and vise versa after the time settled by the user. It uses two capacitors and two resistors connected with the specific pins in a specific manner.

Bistable Mode of 555 Timer

In this mode of 555 Timer, the pins are connected with two resistors, one capacitor and two switches. The switches turn the state of 555 Timer to high and low and thus we obtained the high and low output waves at a time.

Working of the 555 Timer Police Siren

The working of the 555 Timer Police Siren starts from the Direct Current power supply that is supplied to pins 8 of the 555 Timer.

1. Both of these 555 Timers are in the Astable mode that means their pulse output changes continuously.
2. The 555 Timer at the left produces a pulse that is fed into the right 555 Timer as an input.
3. The values of Resistors control the width of the pulses.
4. The capacitors connected with the 555 Timers charge and discharge without any interval.
5.  At the end, this DC power supply enters the speaker with a continuously varying pulses of the current and produces a special sound.
6. If you want to change the output voice, you can change the values of Resistors and capacitors.

Circuit design of 555 Timer Police Siren in Proteus

To design this circuit, simply follow these step given next as it is.

• Start the Proteus Software.
• Choose the required devices from the pick library by clicking the "P" button and writing the names of the devices.

Required Components fpr 555 Timer Police Siren:

1. NE555 Timer (We'll use 2 ICs)
2. Diode
3. Resistor
4. Direct current power supply
5. Speaker
6. Capacitor

• Get the 555 Timer from the library and arrange it at the working area.
• Repeat the step above.
• Choose Resistor, capacitor, Diode and speaker and arrange them on the screen.
• Change the alignment of 4 resistors and diode by left click on screen> Rotate Clockwise and set the whole circuit as shown in the figure:
• Go to Generation Mode>DC and fix it at above the working area.

DID YOU KNOW ???

"If you have the Proteus 8 software, then you can have a real time Siren sound by choosing the Speaker and a piano symbol with it."

• Label the Components by double-clicking it because Proteus throws an error for the duplicate devices.
• Double click the components mentioned below and change their values according to the table given next:

Device	Value
R2	68k Ohm
R3	68K Ohm
R4	8.2K Ohm
R5	8.2K Ohm
C1	100uF
C2	100nF
C3	0.01uF
C4	10uF
Vcc	4V

 

• Go to Terminal Mode>Ground and Set the Ground terminal just below the circuit.

•  Join the 555 Timer's pins with the components as described above in the 555 Timer section.

• Pop the Play button and simulate the circuit.

Task

Now, change the values of capacitor and resistor in different sequence to have the different voices as an output.

Have you heard the siren? If yes then cool. Yet, if no, then look at the circuit deeply and fix the mistake. Truss, today we saw that what is the Police Siren, how does the 555 Timer circuit works, what is the working mechanism of the 555 Timer Police Siren, how does we design the circuit of 555 Timer Police Siren in the Proteus. If you found it useful, give us feedback. If you faced any difficulty, share with us i the comment section. Stay with us with more Proteus Projects.