This lesson will help us understand charge, moving electrons, lightning, current, alternating current and direct current electricity, DC battery, electric potential energy, significance of potential difference, creating potential difference using DC batteries among others.
In this unit we will also learn how to measure voltage using a multimeter, besides creating a lemon battery and measuring its voltage.
Every electrical or electronic device is designed to take a certain amount of current. What will happen if we pass too much current through it?
Every electrical device is rated according to the amount of current it can handle. If we pass too much current (greater than the rated value) through a device, the internal circuitry will get damaged, and the device will stop working. Thus, it is important to control the amount of current in a circuit. The component which can help us do so is a resistor.
For instance, if the floor is too smooth, it will be difficult for us to walk. So, the floor needs some roughness, i.e friction, to enable us to walk. Similarly, in electricity, we need some friction so that we can control the amount of current.
As the name suggests, resistors resist the flow of current through them. We can think of resistors as brakes for electrons. Resistors are one of the primary building blocks of circuits. This ability of a resistor to resist the flow of electrons is called resistance. So, we say that a resistor offers resistance.
In this unit, let’s learn all about resistors and resistance in detail.
LEDS are really fascinating. They are everywhere from televisions to mobile phones. The basics of using an LED is simple. Usual tendency is to connect LEDs directly to a power source. But we just cannot power up LEDs using any random voltage. We need to know the operating voltages for which the LEDs are designed for.
Another important skill is to test out the LEDs using a multimeter whether they are working or not. So let’s find out.
In this unit, we will learn about a breadboard, why to use it and how we can connect different components on it to prototype circuits. In fact, we will learn how to light up an LED and verify Kirchhoff’s Voltage Law using a multimeter.
In addition, we will learn how to use a wire cutter and stripper, a tool which is inevitable for all engineers.
We have learned about voltage, current and resistance and how to measure them using a multimeter. Now, it’s time to define the relationship of all the three.
The current flowing through a component can be calculated if the voltage drop across it and its resistance are known.
We know that Ohm’s Law is:
V = R x I,
where V is the voltage drop across the component measured in volts, I is the current passing through the component measured in ampere, and R is the resistance of the component measured in Ohm.
Now the million dollar question is, was Ohm’s law originally invented to calculate current in a circuit?
Let’s delve deeper to find out.
We have learned how to glow an LED. We know that the intensity with which the LED glows depends upon the amount of current passing through it. This means if we are able to vary the amount of current in a circuit, we can control the intensity of an LED. Now to vary the amount of current, we must control the resistance.
So is there a device using which we can control the amount of resistance in the circuit?Yes, we are talking about variable resistors.
Potentiometer is one such variable resistor, the resistance of which can be measured mechanically. Fan regulators and volume controls in stereos and radios are examples of potentiometers.
Let us give it a bit more twist. How about controlling the resistance using light? Wondering what would that be? Let’s find out!
A buzzer converts electrical energy into sound energy. It is used as an audio indicator, which may be mechanical, electromechanical or electronic. Typical applications include timers and alarms. It is also called a beeper. Let’s try to understand why does a buzzer beep and how do we beep a buzzer.
Every electrical device that we use in our daily lives consumes power to do useful work. There are different ways of combining these electrical devices to distribute power. Two such ways of combining these devices are in series and in parallel.
This lesson will teach us about connecting different components in series and in parallel. Also, we will learn to verify two important Kirchhoff’s Laws: Kirchhoff’s Voltage Law (KVL) and Kirchhoff’s Current Law (KCL).
In this module, we will crack the basics of how a switch works and then we will use an SPDT switch to control LED lights in different ways.
For most people, a switch is a simple ON-OFF device. But it’s much more than that. We will understand the concepts of pole and throw, how different switches work and then try out their applications in real-world projects. Also, we will learn to use a multimeter to test out any switch and find out how it works.
We often see capacitors in circuits and wonder how they work. As textbook says, capacitors are devices that store electrical energy in the form of charge when electric current is passed through them.
As we have seen, a resistor causes a voltage drop in the circuit and converts electrical energy to heat energy, which we often call it Joule Heat. In a way, resistors are consuming electrical energy and convert them into heat. But capacitors are a different animal. Instead of consuming, capacitors store the same energy within itself, something like a reservoir of charge. What can we potentially do with devices that store energy? May be use them later when we need them.
The most important application that will surprise us is that since capacitors take time to either charge or discharge, we can use combination of different capacitors and resistors to create “Time” in circuits.
In this unit, we will work with different types of capacitors, understand their physical construction, analyze the relation between charge and voltage and get into the depths of time constant.
In this unit, we will learn everything about relays. Well, the first question is why relays are so important? Do you know that relays are used in your car in at least 20 different places?
Relays drive the power lights (headlamps and tail lamps) and control horns and wiper motion. In industries, they drive motors, pumps and compressors. In homes, refrigerators and air conditioners use relays to control the compressor.
This module will stress on how we built such an important device by combining the concepts of switching and electromagnetism. We will also build an electromagnet and learn to test and use a relay in a variety of applications, including the burglar alarm, and oscillator. This module is full of fun and new knowledge that would further strengthen your concepts of electromagnetism and its real-world applications.
In electronics, we study the properties of materials to design devices which can control the flow of electrons. Broadly, the materials fall into three categories: conductors, insulators, and semiconductors. We have already learned about conductors and insulators. Now, we will learn about semiconductors.
We cannot imagine a world without mobile phones, computers, televisions and refrigerators. The modern electronics world was made possible by semiconductors. Let’s delve deeper into the world of semiconductors in this lesson.
In this unit, we will practically implement four digital logic gates using a combination of diodes and resistors. The most common type of gates are NOT, OR, AND, NOR and NAND. But what are they?
To give you a brief overview, logic gates are the building blocks of digital devices and help them compute in the blink of an eye. Any logic gate is a circuit which works on a pre-defined logic to produce an output. A logic gate may have one or more inputs, but it produces only one output. So think of logic as an input-output system. And you can design this system all by yourself if you know the basics.
Did you know that by using a combination of a few NAND Gates, you can actually create an Electronic Door Lock System wherein you can set your own code and the door lock opens up with the right combination of keys? That is the beauty of doing the right connections in hardware. If you do the connections right, you can do a lot of amazing stuff.
So let’s get started!
Zener diode! Hmm…The name itself tells us that this is a diode and it will conduct in only one direction. But wait! this diode conducts in both directions. Then why do we even call it a diode?
This is a specially designed diode which starts conducting in reverse-bias mode only under certain conditions and we will find out about those conditions. The bigger question is why do we even need zener diodes? Well if there would be no zener diodes, all our electrical appliances at home would either get fried (zapped) or fused. Sounds interesting?
In this module, you will learn everything about zener diodes, how they work and how to use them. In addition, we will again work on how to build a voltage divider.
Don’t get confused between voltage divider and voltage regulator.
DC motors are a fascinating piece of engineering. From robots to automobiles to vacuum cleaners to fans to printers to blenders, we can find motors almost everywhere to create motion. And this motion is always not necessarily circular as most people often tend to think.
In this module, we will learn how DC motors work, their physical construction, how they rotate, what physics laws govern their working, what factors affect their speed and torque (rotational force) and their applications.
We will also do a surgery of a motor and label its parts.
For all aspiring engineers, designers and roboticist, this module is a must-have.
The term transistor is derived from transfer and resistance. A transistor acts as a resistor which can amplify electrical signals as they are transferred through it from input to output.
Sounds very bookish and technical? Don’t get overwhelmed. You will see that we will make it extremely simple for you as you start to develop a deeper understanding about transistors.
In this module, we will discuss about the history of transistors, what transistors look like, how to identify its terminals, both manually and using a multimeter, its significance and applications, how to turn it ON and how to get an output current from it and more. Essentially, you will develop a more holistic understanding about what a transistor is and how it works before you start working on its applications.
So let’s get started.
In this module, you will build a range of very interesting projects using transistors from touch-activated switch to automatic night lamp to LED Flasher (Blinker) to H-Bridge (motor driving circuit used in robotics) among others. In addition, you will master the art of using a transistor as an an amplifier and switch. This module is completely application-based and you will have an enjoyable experience.
This is an advanced module for STEM teachers who would like to go into the further depths of electricity concepts. We have intentionally kept the pace of these videos a bit slower so that viewers can stop and ponder over what is being said in the videos.
In this module, we will discuss about electric potential, electric potential energy, how potential difference between two points creates voltage, how one can apply the definition of electric potential to positive and negative terminals of a battery, what is the meaning of 9 volt in a battery and the phenomenon of lightning.
In this assignment, you are required to create a new and original project based on what you have learned so far. You will be judged on the novelty of your idea and its implementation.
In this module, we will focus on our premium projects, including Infrared (IR) security alarm, Joule thief and Temperature sensor.