Ohm's Law Calculations for Circuit Analysis Quiz…

Q: A series circuit has a voltage source of 24V and three resistors: R1 = 2 Ohms, R2 = 3 Ohms, and R3 = 7 Ohms. What is the current flowing through R2?

2 A — In a series circuit, current is the same throughout. Total resistance is 12 ohms; current is V/R = 24V/12 Ohms = 2A.

Q: A parallel circuit has three branches. Branch 1 has a 12V source and a 4 Ohm resistor. Branch 2 has a 12V source and a 6 Ohm resistor. Branch 3 has a 12V source and a 3 Ohm resistor. What is the total current supplied by the source?

9 A — Calculate current in each branch (3A, 2A, 4A). Total current is the sum of branch currents: 9A.

Q: A 100-watt light bulb operates on a 120V power supply. What is the resistance of the light bulb filament?

144 Ohms — Use P=V^2/R. Rearrange: R = V^2/P = 120^2/100 = 144 Ohms.

Q: What is the voltage drop across a 50 Ohm resistor if 0.5 Amperes of current is flowing through it?

25 V — Use Ohm's Law: V = I * R = 0.5 A * 50 Ohms = 25V.

Q: A circuit contains a 9V battery and a 330 Ohm resistor. What is the power dissipated by the resistor?

0.245 W — Calculate current (I = V/R = 9/330 A). Then power: P = V*I= 9 * (9/330) ? 0.245 W.

Q: If a resistor dissipates 5 Watts of power with a 10V voltage drop across it, what is the resistance of the resistor?

20 Ohms — Use P=V^2/R. Rearrange: R = V^2/P = 10^2/5 = 20 Ohms.

Q: Two resistors, 10 Ohms and 20 Ohms, are connected in series across a 12V source. What is the voltage drop across the 20 Ohm resistor?

8 V — Total resistance is 30 Ohms. Current: I = V/R = 12/30 = 0.4A. V = I*R = 0.4A * 20 Ohms = 8V.

Q: A parallel circuit has three resistors with values of 10 Ohms, 20 Ohms and 30 Ohms. The voltage source is 60V. What is the current through the 10 Ohm resistor?

6 A — In a parallel circuit, voltage is same across each branch. Current through 10 Ohm resistor: I = V/R = 60V/10 Ohms = 6A.

Q: Calculate the equivalent resistance of two resistors, 4 Ohms and 12 Ohms, connected in parallel.

3 Ohms — Use 1/R_eq = 1/R1 + 1/R2. 1/R_eq = 1/4 + 1/12 = 1/3, therefore R_eq = 3 Ohms.

Q: In a simple circuit with a battery and a resistor, if the voltage doubles and the resistance remains constant, what happens to the current?

It doubles — Ohm's Law: I = V/R. If V doubles and R stays the same, I doubles.

Question 1 of 10

A series circuit has a voltage source of 24V and three resistors: R1 = 2 Ohms, R2 = 3 Ohms, and R3 = 7 Ohms. What is the current flowing through R2?

In a series circuit, current is the same throughout. Total resistance is 12 ohms; current is V/R = 24V/12 Ohms = 2A.

Question 2 of 10

A parallel circuit has three branches. Branch 1 has a 12V source and a 4 Ohm resistor. Branch 2 has a 12V source and a 6 Ohm resistor. Branch 3 has a 12V source and a 3 Ohm resistor. What is the total current supplied by the source?

Calculate current in each branch (3A, 2A, 4A). Total current is the sum of branch currents: 9A.

Question 3 of 10

A 100-watt light bulb operates on a 120V power supply. What is the resistance of the light bulb filament?

Use P=V^2/R. Rearrange: R = V^2/P = 120^2/100 = 144 Ohms.

Question 4 of 10

What is the voltage drop across a 50 Ohm resistor if 0.5 Amperes of current is flowing through it?

Use Ohm's Law: V = I * R = 0.5 A * 50 Ohms = 25V.

Question 5 of 10

A circuit contains a 9V battery and a 330 Ohm resistor. What is the power dissipated by the resistor?

Calculate current (I = V/R = 9/330 A). Then power: P = V*I= 9 * (9/330) ? 0.245 W.

Question 6 of 10

If a resistor dissipates 5 Watts of power with a 10V voltage drop across it, what is the resistance of the resistor?

Use P=V^2/R. Rearrange: R = V^2/P = 10^2/5 = 20 Ohms.

Question 7 of 10

Two resistors, 10 Ohms and 20 Ohms, are connected in series across a 12V source. What is the voltage drop across the 20 Ohm resistor?

Total resistance is 30 Ohms. Current: I = V/R = 12/30 = 0.4A. V = I*R = 0.4A * 20 Ohms = 8V.

Question 8 of 10

A parallel circuit has three resistors with values of 10 Ohms, 20 Ohms and 30 Ohms. The voltage source is 60V. What is the current through the 10 Ohm resistor?

In a parallel circuit, voltage is same across each branch. Current through 10 Ohm resistor: I = V/R = 60V/10 Ohms = 6A.

Question 9 of 10

Calculate the equivalent resistance of two resistors, 4 Ohms and 12 Ohms, connected in parallel.

Use 1/R_eq = 1/R1 + 1/R2. 1/R_eq = 1/4 + 1/12 = 1/3, therefore R_eq = 3 Ohms.

Question 10 of 10

In a simple circuit with a battery and a resistor, if the voltage doubles and the resistance remains constant, what happens to the current?

Ohm's Law: I = V/R. If V doubles and R stays the same, I doubles.

Ohm's Law Calculations for Circuit Analysis Quiz