Understanding Ohm's Law in Electric Circuits

What is the current (I) when voltage (V) is 110 V and resistance (R) is 550 Ω?

If the resistance (R) is 100 Ω and the current (I) is 0.5 A, what is the voltage (V)?

What is the resistance (R) when voltage (V) is 230 V and current (I) is 1.2 A?

When voltage (V) is 24 V and resistance (R) is 10 kΩ, what is the current (I)?

Which of the following correctly represents 100000 microamperes (µA) in Amperes (A)?

How many kilo-ohms are in 20,000 ohms?

What is the value of I if V is 30 V and R is 15 Ω?

If a circuit has a voltage of 300 V and draws a current of 0.3 A, what is the resistance?

What does Ohm's law state about the relationship between voltage, current, and resistance?

If the current in a circuit is 2 A and the resistance is 10 Ω, what is the voltage across the load?

In a circuit, if the voltage is increased while keeping the resistance constant, what happens to the current?

What is the value of the current drawn from a supply of 230 V with a load resistance of 500 Ω?

If you connect a voltmeter in a circuit, what does it measure?

What would happen to the current in a circuit if the resistance is doubled while the voltage remains the same?

Ohm's law is used to calculate which of the following?

In the formula V = I × R, which variable represents resistance?

Understanding Ohm's Law

Ohm's law defines the relationship between voltage (V), current (I), and resistance (R) in an electric circuit with the formula V = I × R.
Voltage (V) is measured in volts (V), current (I) in amperes (A), and resistance (R) in ohms (Ω).
This law illustrates that current flowing through a conductor is directly proportional to the voltage applied, assuming constant temperature.

Application of Ohm's Law

To determine voltage, current, or resistance in a circuit, use rearranged formulas:
- Voltage: V = I × R
- Current: I = V / R
- Resistance: R = V / I

Ohm's Discovery

Georg Simon Ohm discovered the fundamental relationship in electric circuits leading to the formulation of Ohm’s law.
The significance lies in the ability to analyze and predict behavior in electrical circuits.

Worked Examples

Example to calculate Voltage:
- Given I = 0.5 A and R = 20 Ω, V = 0.5 A × 20 Ω = 10 V.
Example to calculate Current:
- For a load with R = 500 Ω connected to a 230 V supply, I = 230 V / 500 Ω = 0.46 A.

Units of Measurement

Common electrical units:
- micro (M): 1 M = 0.001 A
- kilo (k): 1 k = 1000 Ω
- Mega (M): 1 M = 1,000,000 Ω

Practice Questions

Engage with practice problems to reinforce understanding of Ohm's law:
- Calculate voltage if I = 0.5 A and R = 100 Ω. Result: V = 50 V.
- Find current if V = 110 V and R = 550 Ω. Result: I = 0.2 A.
- Determine resistance if V = 230 V and I = 1.2 A. Result: R ≈ 191.67 Ω.
- Compute current if V = 24 V and R = 10 kΩ. Result: I = 0.0024 A.

This quiz focuses on Ohm's Law, exploring the relationship between voltage, current, and resistance. Participants will apply the formula V=I × R, connect basic electric circuits, and verify their understanding of these fundamental concepts. Ideal for students studying electricity and circuits.