Circuits & Kirchhoff Laws for Competitive Exam Prep

Circuits & Kirchhoff Laws

Q. In a circuit with a 12V battery and two resistors of 4Ω and 8Ω in series, what is the current flowing through the circuit?

A. 0.5A
B. 1A
C. 1.5A
D. 2A

Solution

Total resistance R = R1 + R2 = 4Ω + 8Ω = 12Ω. Current I = V/R = 12V / 12Ω = 1A.

Correct Answer: B — 1A

Learn More →

Q. In a circuit with a 12V battery and two resistors of 4Ω and 8Ω in series, what is the voltage across the 8Ω resistor?

A. 4V
B. 6V
C. 8V
D. 12V

Solution

Using the voltage divider rule, V = (R2 / (R1 + R2)) * Vtotal = (8 / (4 + 8)) * 12 = 8V.

Correct Answer: C — 8V

Learn More →

Q. In a circuit with a 15V battery and three resistors (5Ω, 10Ω, and 15Ω) in parallel, what is the equivalent resistance?

A. 2Ω
B. 3Ω
C. 5Ω
D. 10Ω

Solution

1/R_eq = 1/5 + 1/10 + 1/15 = 0.1 + 0.0667 + 0.0667 = 0.2334. Therefore, R_eq = 4.29Ω.

Correct Answer: B — 3Ω

Learn More →

Q. In a circuit with a 15V battery and two resistors in series (5Ω and 10Ω), what is the voltage drop across the 10Ω resistor?

A. 5V
B. 10V
C. 15V
D. 20V

Solution

Using the voltage divider rule, V2 = (R2 / (R1 + R2)) * Vtotal = (10 / (5 + 10)) * 15 = 10V.

Correct Answer: B — 10V

Learn More →

Q. In a circuit with a 15V battery and two resistors in series (R1 = 5Ω, R2 = 10Ω), what is the voltage across R2?

A. 10V
B. 5V
C. 15V
D. 0V

Solution

Voltage across R2 = (R2 / (R1 + R2)) * V = (10Ω / (5Ω + 10Ω)) * 15V = 10V.

Correct Answer: A — 10V

Learn More →

Q. In a circuit with a 20V battery and two resistors (4Ω and 8Ω) in parallel, what is the total current supplied by the battery?

A. 2A
B. 3A
C. 4A
D. 5A

Solution

Total resistance in parallel, 1/Req = 1/R1 + 1/R2 = 1/4 + 1/8 = 3/8. Therefore, Req = 8/3Ω. Total current I = V/Req = 20V / (8/3) = 7.5A.

Correct Answer: C — 4A

Learn More →

Q. In a circuit with a 24V battery and three resistors (R1 = 4Ω, R2 = 4Ω, R3 = 4Ω) in parallel, what is the total current supplied by the battery?

A. 2A
B. 3A
C. 4A
D. 6A

Solution

Equivalent resistance R_eq = 1/(1/R1 + 1/R2 + 1/R3) = 1/(1/4 + 1/4 + 1/4) = 1.33Ω. Total current I = V/R_eq = 24V/1.33Ω = 18A.

Correct Answer: D — 6A

Learn More →

Q. In a circuit with a 24V battery and three resistors in parallel (4Ω, 6Ω, and 12Ω), what is the total current supplied by the battery?

A. 2A
B. 3A
C. 4A
D. 6A

Solution

1/R_eq = 1/4 + 1/6 + 1/12 = 1. Therefore, R_eq = 2Ω. Total current I = V/R_eq = 24V/2Ω = 12A.

Correct Answer: C — 4A

Learn More →

Q. In a circuit with a 24V battery and three resistors in series (R1 = 2Ω, R2 = 3Ω, R3 = 5Ω), what is the voltage drop across R2?

A. 6V
B. 8V
C. 12V
D. 10V

Solution

Total resistance R_total = R1 + R2 + R3 = 2Ω + 3Ω + 5Ω = 10Ω. Current I = V/R_total = 24V / 10Ω = 2.4A. Voltage drop across R2 = I * R2 = 2.4A * 3Ω = 7.2V.

Correct Answer: B — 8V

Learn More →

Q. In a circuit with a 24V battery and three resistors of 2 ohms, 4 ohms, and 6 ohms in series, what is the total current flowing through the circuit?

A. 2 A
B. 3 A
C. 4 A
D. 1 A

Solution

Total resistance R = 2 + 4 + 6 = 12 ohms. Using Ohm's law, I = V/R = 24V / 12 ohms = 2 A.

Correct Answer: B — 3 A

Learn More →

Q. In a circuit with a 24V battery and three resistors of 4Ω, 4Ω, and 8Ω in series, what is the voltage drop across the 8Ω resistor?

A. 8V
B. 12V
C. 16V
D. 24V

Solution

Total resistance R = 4Ω + 4Ω + 8Ω = 16Ω. Current I = V/R = 24V/16Ω = 1.5A. Voltage drop across 8Ω = I * R = 1.5A * 8Ω = 12V.

Correct Answer: B — 12V

Learn More →

Q. In a circuit with a 24V battery and two resistors in series (4Ω and 8Ω), what is the voltage across the 8Ω resistor?

A. 8V
B. 12V
C. 16V
D. 20V

Solution

Voltage across 8Ω resistor = (R2 / (R1 + R2)) * Vtotal = (8 / (4 + 8)) * 24 = 16V.

Correct Answer: B — 12V

Learn More →

Q. In a circuit with a 24V battery and two resistors in series (6Ω and 3Ω), what is the voltage across the 3Ω resistor?

A. 8V
B. 12V
C. 16V
D. 4V

Solution

Total resistance = 6Ω + 3Ω = 9Ω. Current I = V / R = 24V / 9Ω = 2.67A. Voltage across 3Ω = I * R = 2.67A * 3Ω = 8V.

Correct Answer: A — 8V

Learn More →

Q. In a circuit with a 24V battery and two resistors in series (R1 = 6Ω, R2 = 12Ω), what is the voltage drop across R2?

A. 12V
B. 18V
C. 6V
D. 8V

Solution

Voltage drop across R2 = V_R2 = (R2 / (R1 + R2)) * V_total = (12Ω / (6Ω + 12Ω)) * 24V = 12V.

Correct Answer: A — 12V

Learn More →

Q. In a circuit with a 24V battery and two resistors in series (R1 = 8Ω, R2 = 16Ω), what is the current flowing through the circuit?

A. 1A
B. 2A
C. 3A
D. 4A

Solution

Total resistance R_total = R1 + R2 = 8Ω + 16Ω = 24Ω. The current is I = V/R_total = 24V / 24Ω = 1A.

Correct Answer: B — 2A

Learn More →

Q. In a circuit with a 24V battery and two resistors in series (R1 = 8Ω, R2 = 16Ω), what is the voltage across R2?

A. 16V
B. 8V
C. 12V
D. 4V

Solution

Using voltage division, V_R2 = V_total * (R2 / (R1 + R2)) = 24V * (16Ω / (8Ω + 16Ω)) = 16V.

Correct Answer: A — 16V

Learn More →

Q. In a circuit with a 24V battery and two resistors of 8Ω and 4Ω in series, what is the voltage across the 4Ω resistor?

A. 6V
B. 8V
C. 12V
D. 16V

Solution

Using the voltage divider rule, V_R2 = (R2 / (R1 + R2)) * Vtotal = (4 / (8 + 4)) * 24 = 8V.

Correct Answer: C — 12V

Learn More →

Q. In a circuit with a 5V battery and two resistors in parallel (5Ω and 10Ω), what is the current through the 10Ω resistor?

A. 0.5A
B. 1A
C. 1.5A
D. 2A

Solution

Using Ohm's Law, I = V/R = 5V / 10Ω = 0.5A.

Correct Answer: B — 1A

Learn More →

Q. In a circuit with a 9V battery and three resistors (3Ω, 3Ω, and 3Ω) in series, what is the voltage across each resistor?

A. 3V
B. 6V
C. 9V
D. 1V

Solution

In a series circuit, the voltage is divided equally among the resistors. Therefore, V across each 3Ω resistor = 9V / 3 = 3V.

Correct Answer: A — 3V

Learn More →

Q. In a circuit with a 9V battery and three resistors in series (2Ω, 3Ω, and 5Ω), what is the total resistance?

A. 5Ω
B. 8Ω
C. 10Ω
D. 15Ω

Solution

Total resistance R = R1 + R2 + R3 = 2Ω + 3Ω + 5Ω = 10Ω.

Correct Answer: C — 10Ω

Learn More →

Q. In a circuit with a 9V battery and three resistors of 3Ω, 3Ω, and 6Ω in parallel, what is the total current supplied by the battery?

A. 1A
B. 2A
C. 3A
D. 4A

Solution

1/R_eq = 1/3 + 1/3 + 1/6 = 1. Therefore, R_eq = 1Ω. Total current I = V/R_eq = 9V/1Ω = 9A.

Correct Answer: C — 3A

Learn More →

Q. In a circuit with a 9V battery and two resistors (R1 = 3Ω, R2 = 6Ω) in series, what is the current flowing through the circuit?

A. 1A
B. 2A
C. 3A
D. 0.5A

Solution

Total resistance R_total = R1 + R2 = 3Ω + 6Ω = 9Ω. Current I = V/R = 9V/9Ω = 1A.

Correct Answer: B — 2A

Learn More →

Q. In a circuit with a 9V battery and two resistors in series (R1 = 3Ω, R2 = 6Ω), what is the voltage across R2?

A. 6V
B. 3V
C. 9V
D. 0V

Solution

Using voltage division, V_R2 = (R2 / (R1 + R2)) * V_total = (6Ω / (3Ω + 6Ω)) * 9V = 6V.

Correct Answer: A — 6V

Learn More →

Q. In a circuit with a 9V battery and two resistors of 3 ohms and 6 ohms in series, what is the voltage drop across the 6 ohm resistor?

A. 6V
B. 3V
C. 9V
D. 4.5V

Solution

The total resistance is 9 ohms. The current is I = V/R = 9V / 9 ohms = 1 A. The voltage drop across the 6 ohm resistor is V = I * R = 1 A * 6 ohms = 6V.

Correct Answer: A — 6V

Learn More →

Q. In a circuit with three resistors in series (2 ohms, 3 ohms, and 5 ohms), what is the total resistance?

A. 10 ohms
B. 5 ohms
C. 3 ohms
D. 2 ohms

Solution

For resistors in series, R_total = R1 + R2 + R3 = 2 + 3 + 5 = 10 ohms.

Correct Answer: A — 10 ohms

Learn More →

Q. In a circuit with three resistors R1, R2, and R3 connected in series, if R1 = 2Ω, R2 = 3Ω, and R3 = 5Ω, what is the total resistance?

A. 5Ω
B. 10Ω
C. 8Ω
D. 3Ω

Solution

Total resistance in series is R_total = R1 + R2 + R3 = 2Ω + 3Ω + 5Ω = 10Ω.

Correct Answer: B — 10Ω

Learn More →

Q. In a circuit with two loops, if the current in the first loop is 2 A and in the second loop is 3 A, what is the total current entering a junction where these loops meet?

A. 1 A
B. 5 A
C. 6 A
D. 2 A

Solution

According to Kirchhoff's current law, the total current entering a junction equals the total current leaving it. Therefore, total current = 2 A + 3 A = 5 A.

Correct Answer: B — 5 A

Learn More →

Q. In a circuit with two loops, if the current in the first loop is 5 A and the second loop is 3 A, what is the current through a shared resistor of 2 ohms?

A. 1 A
B. 2 A
C. 3 A
D. 5 A

Solution

The current through the shared resistor is the difference of the currents in the loops, so 5 A - 3 A = 2 A.

Correct Answer: A — 1 A

Learn More →

Q. In a circuit with two resistors in parallel, if one resistor is 4 ohms and the other is 6 ohms, what is the equivalent resistance?

A. 2.4 ohms
B. 10 ohms
C. 24 ohms
D. 3.6 ohms

Solution

Using the formula for resistors in parallel, 1/R_eq = 1/4 + 1/6, we find R_eq = 2.4 ohms.

Correct Answer: A — 2.4 ohms

Learn More →

Q. In a circuit with two resistors in parallel, if one resistor is 4Ω and the other is 12Ω, what is the total current flowing through the circuit when connected to a 24V battery?

A. 2A
B. 3A
C. 4A
D. 6A

Solution

First, find the equivalent resistance: 1/R_eq = 1/4 + 1/12 = 1/3. R_eq = 3Ω. Then, I = V/R = 24V / 3Ω = 8A.

Correct Answer: D — 6A

Learn More →

Showing 61 to 90 of 154 (6 Pages)

Circuits & Kirchhoff Laws

On a scale of 0–10, how likely are you to recommend The Soulshift Academy?