ClassX Video Lessons Youtube Channel The Engineering Mindset Ohms Law Explained – The basics circuit theory
Welcome! Today, we’re diving into the world of Ohm’s Law to understand how it works and how you can use it in electrical circuits. Ohm’s Law is a fundamental principle in electronics that shows the relationship between voltage, current, and resistance. It was developed by a German physicist named Georg Ohm, who conducted numerous experiments to come up with this theory.
Ohm’s Law can be expressed using three simple formulas:
To make these formulas easier to remember, you can use Ohm’s triangle. Imagine a triangle with V at the top and I and R at the bottom corners. This helps you quickly figure out which formula to use by covering up the letter you want to find.
You might wonder why we use the letter ‘I’ for current instead of ‘C’ or ‘A’. This is because the unit of current is the Ampere, named after André Ampère, a French physicist who did a lot of work with electrical currents.
Let’s look at some examples to see how these formulas work in real-life situations:
Imagine a simple circuit with a battery and a resistor. If the resistor has a resistance of 3 Ohms and the current flowing through it is 2 Amps, you can find the voltage using the formula V = I × R. By plugging in the values, you get:
Voltage = 2 Amps × 3 Ohms = 6 Volts
If you double the voltage by connecting two 6-volt batteries in series, the current also doubles from 2 Amps to 4 Amps. This shows that current is directly proportional to voltage.
Now, let’s find the current. If you have a lamp with a resistance of 3 Ohms connected to a 6-volt power supply, you can use the formula I = V ÷ R. With a voltage of 6 volts, the current is:
Current = 6 Volts ÷ 3 Ohms = 2 Amps
If the resistance increases to 6 Ohms, the current decreases to 1 Amp, demonstrating that current is inversely proportional to resistance.
Finally, let’s calculate resistance. If a lamp is connected to a 12-volt power supply and the current is measured at 0.5 Amps, you can find the resistance using R = V ÷ I:
Resistance = 12 Volts ÷ 0.5 Amps = 24 Ohms
Now it’s your turn to practice! Try solving these problems:
That’s all for now! Keep exploring and learning more about electronics. For more resources, visit theengineeringmindset.com and follow them on social media.
Use the Ohm’s Law triangle to solve a series of puzzles. Each puzzle will give you two values (voltage, current, or resistance), and you need to find the third. Write down your answers and check them with your classmates to see who gets the most correct!
Gather some basic circuit components like batteries, wires, and resistors. Build a simple circuit and use a multimeter to measure the voltage, current, and resistance. Apply Ohm’s Law to verify your measurements and discuss any discrepancies with your teacher.
In groups, create a short skit where each member represents voltage, current, or resistance. Act out scenarios showing how changes in one affect the others. Present your skit to the class and explain the relationships using Ohm’s Law.
Use an online circuit simulator to experiment with different circuit configurations. Adjust the voltage, current, and resistance values to see how they affect each other. Take screenshots of your findings and write a short report on your observations.
Participate in a quiz competition where you’ll answer questions related to Ohm’s Law. Work in teams to solve problems quickly and accurately. The team with the most correct answers wins a small prize!
Sure! Here’s a sanitized version of the YouTube transcript:
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– Hey there, everyone! Paul here from theengineeringmindset.com. In this video, we’re going to explore Ohm’s Law to understand how it works and how to use it. There are also two problems at the end of this video for you to test your knowledge.
So, what is Ohm’s Law? Ohm’s Law describes the relationship between voltage, current, and resistance. It was developed by German physicist Georg Ohm, who conducted many experiments to formulate his theory.
There are three formulas we use for Ohm’s Law:
1. Voltage (V) = Current (I) × Resistance (R)
2. Current (I) = Voltage (V) ÷ Resistance (R)
3. Resistance (R) = Voltage (V) ÷ Current (I)
If that seems like a lot to remember, don’t worry! We can simplify it with Ohm’s triangle. Just remember the letters V, I, and R in that order. You can visualize it as a triangle with V at the top.
You don’t even need to memorize the formulas because I’ve created a free PDF guide with worked examples that you can keep on your PC or mobile device. Links for that can be found in the video description below.
When we need to use a formula, we cover up the letter we need. For example, if we want to find voltage, we cover up V in the triangle, leaving us with I and R. This means voltage equals current multiplied by resistance.
You might wonder why current is represented by the letter I instead of C or A. The unit of current is the Ampere, named after French physicist André Ampère, who conducted many experiments involving electrical current.
Now, let’s look at some examples of how to use these formulas.
First, let’s find voltage in a simple circuit with a battery and a resistor. If the resistor is 3 Ohms and the current is 2 Amps, we can use Ohm’s triangle to find the voltage. By covering up V, we get V = I × R. Plugging in the values, we find that the voltage is 6 volts.
If we double the voltage by connecting two 6-volt batteries in series, the current also doubles from 2 Amps to 4 Amps. This shows that current is directly proportional to voltage.
Now, let’s find current. If we have a 3 Amp lamp connected to a 6-volt power supply, we can find the current by using the formula I = V ÷ R. If the voltage is 6 volts and the resistance is 3 Ohms, the current is 2 Amps.
If we increase the resistance to 6 Ohms, the current halves to 1 Amp. This demonstrates that current is inversely proportional to resistance.
Finally, let’s find resistance. If we have a lamp connected to a 12-volt power supply and measure the current at 0.5 Amps, we can find the resistance using R = V ÷ I. This gives us 24 Ohms of resistance.
Now it’s time for you to test your skills! Here are two problems:
1. A lamp has a resistance of 240 Ohms. If plugged into a 120-volt outlet, what will the current be?
2. If the same 240 Ohm lamp is plugged into a UK outlet and the current is 0.958 Amps, what is the voltage being applied?
That’s it for this video! To continue your learning, check out one of the videos on the screen now. Don’t forget to follow us on social media and visit theengineeringmindset.com.
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This version removes any informal language, personal anecdotes, and extraneous details while retaining the educational content.
Ohm’s Law – A fundamental principle in physics that states the current through a conductor between two points is directly proportional to the voltage across the two points and inversely proportional to the resistance. – Example sentence: Using Ohm’s Law, the engineer calculated the current flowing through the circuit.
Voltage – The electric potential difference between two points, which causes electric charges to flow in a circuit. – Example sentence: The battery provides a voltage of 9 volts to power the electronic device.
Current – The flow of electric charge in a circuit, typically measured in amperes (amps). – Example sentence: The current flowing through the wire was measured to be 2 amps.
Resistance – A measure of how much a material opposes the flow of electric current, typically measured in ohms. – Example sentence: The resistance of the resistor was 10 ohms, which limited the current in the circuit.
Circuit – A closed loop that allows electric current to flow, consisting of a power source, conductors, and other electrical components. – Example sentence: The students built a simple circuit using a battery, wires, and a light bulb.
Amps – The unit of measurement for electric current, representing the amount of charge passing a point in a circuit per second. – Example sentence: The circuit breaker can handle up to 15 amps before it trips.
Physicist – A scientist who studies and specializes in the field of physics, exploring the properties and interactions of matter and energy. – Example sentence: The physicist conducted experiments to understand the behavior of electrons in different materials.
Electronics – The branch of physics and engineering that deals with the study and application of electronic devices and circuits. – Example sentence: The electronics lab was filled with various components like resistors, capacitors, and transistors.
Formulas – Mathematical equations used to calculate and predict physical quantities in physics and engineering. – Example sentence: The students used formulas to calculate the speed of the car in their physics project.
Triangle – A geometric shape with three sides and three angles, often used in physics to represent vector components or in engineering to analyze forces. – Example sentence: The force triangle helped the engineer determine the resultant force acting on the structure.
