Ohm's Law Quiz with Answers: Test Your Physics Knowledge

📚 Quick Study Guide

• 💡 Ohm's Law defines the relationship between voltage (V), current (I), and resistance (R) in an electrical circuit.
• 🔢 The formula for Ohm's Law is: $V = IR$, where:
• $V$ = Voltage (measured in volts)
• $I$ = Current (measured in amperes)
• $R$ = Resistance (measured in ohms)
• 🧪 Resistance (R) is the opposition to the flow of electric current in a circuit.
• ⚡️ Current (I) is the rate of flow of electric charge past a point or region.
• 🔋 Voltage (V) is the electric potential difference, also known as electromotive force, measured in volts.
• 📐 Rearrangements of the formula: $I = \frac{V}{R}$ and $R = \frac{V}{I}$.
• 📝 Power (P) in a circuit can be calculated using Ohm's Law and is given by: $P = VI = I^2R = \frac{V^2}{R}$.

Practice Quiz

1. What is the voltage across a 4-ohm resistor if a current of 2 amperes is flowing through it?

   1. 4 V
   2. 6 V
   3. 8 V
   4. 10 V

2. A circuit has a voltage of 12V and a resistance of 6 ohms. What is the current flowing through the circuit?

   1. 0.5 A
   2. 1 A
   3. 2 A
   4. 3 A

3. What is the resistance of a heating element that draws 5A from a 110V supply?

   1. 11 ohms
   2. 22 ohms
   3. 33 ohms
   4. 44 ohms

4. If the current through a 10-ohm resistor is 3A, what is the voltage drop across the resistor?

   1. 10 V
   2. 20 V
   3. 30 V
   4. 40 V

5. A lightbulb has a resistance of 200 ohms and is connected to a 100V source. What is the current flowing through the lightbulb?

   1. 0.25 A
   2. 0.5 A
   3. 0.75 A
   4. 1 A

6. What happens to the current in a circuit if the voltage is doubled and the resistance remains constant?

   1. The current is halved.
   2. The current remains the same.
   3. The current is doubled.
   4. The current is quadrupled.

7. A device has a power rating of 100W when connected to a 20V source. What is the current drawn by the device?

   1. 2 A
   2. 3 A
   3. 4 A
   4. 5 A