BMST Electrical Circuits and Ohm's Law 2 — Questions and Answers
Question 1: A circuit has a voltage of 24 V and a resistance of 8 Ω. What is the current?
- 2 A
- 3 A (Correct answer)
- 4 A
- 6 A
Correct answer: 3 A
Using Ohm's Law: I = V/R = 24/8 = 3 A.
Question 2: Two resistors of 6 Ω and 12 Ω are connected in parallel. What is the equivalent resistance?
- 18 Ω
- 9 Ω
- 4 Ω (Correct answer)
- 2 Ω
Correct answer: 4 Ω
For parallel resistors: 1/R = 1/6 + 1/12 = 3/12, so R = 4 Ω.
Question 3: A resistor dissipates 50 W of power when 5 A flows through it. What is the resistance?
- 1 Ω
- 2 Ω (Correct answer)
- 5 Ω
- 10 Ω
Correct answer: 2 Ω
Using P = I²R: R = P/I² = 50/25 = 2 Ω.
Question 4: Which component in a circuit is specifically designed to limit current flow?
- Capacitor
- Inductor
- Resistor (Correct answer)
- Diode
Correct answer: Resistor
A resistor is designed to oppose and limit the flow of electric current in a circuit.
Question 5: If voltage across a resistor doubles while resistance stays the same, what happens to power dissipated?
- It doubles
- It halves
- It quadruples (Correct answer)
- It stays the same
Correct answer: It quadruples
Since P = V²/R, doubling V quadruples the power (2² = 4).
Question 6: In a series circuit with three resistors of 3 Ω, 5 Ω, and 7 Ω, what is the total resistance?
- 5 Ω
- 10 Ω
- 15 Ω (Correct answer)
- 21 Ω
Correct answer: 15 Ω
Series resistances add directly: R_total = 3 + 5 + 7 = 15 Ω.
Question 7: A 9 V battery powers a circuit with 3 Ω total resistance. How much power is consumed?
- 3 W
- 9 W
- 27 W (Correct answer)
- 81 W
Correct answer: 27 W
P = V²/R = 81/3 = 27 W.
BMST Electrical Circuits and Ohm's Law 2
A circuit has a voltage of 24 V and a resistance of 8 Ω.
What is the current?