20 Multiple Choice Questions (MCQs) with Answers for Electrical Engineering Students | PART 1

 Whether you're preparing for exams, interviews, or just want to brush up your knowledge, these 20 carefully selected multiple-choice questions (MCQs) cover a wide range of foundational electrical engineering topics including circuits, machines, power systems, and electronics.

1. Ohm’s Law states that:

A) Voltage = Current × Resistance
B) Voltage = Resistance / Current
C) Resistance = Power × Voltage
D) Current = Power × Resistance

✅ Answer: A

2. The unit of electrical capacitance is:

A) Ohm
B) Farad
C) Watt
D) Coulomb

✅ Answer: B

3. Which one is a passive component?

A) Transistor
B) Diode
C) Resistor
D) MOSFET

✅ Answer: C

4. A transformer operates on the principle of:

A) Static Induction
B) Mutual Induction
C) Electrostatic Induction
D) Self Induction

✅ Answer: B

5. Power factor is defined as:

A) True Power / Apparent Power
B) Apparent Power / True Power
C) Real Power × Reactive Power
D) Resistance / Reactance

✅ Answer: A

6. The frequency of the standard AC supply in most countries is:

A) 50 Hz or 60 Hz
B) 100 Hz
C) 25 Hz
D) 75 Hz

✅ Answer: A

7. Kirchhoff’s Voltage Law (KVL) is based on:

A) Conservation of charge
B) Conservation of energy
C) Faraday's law
D) Coulomb’s law

✅ Answer: B

8. The most commonly used material for electrical wire conductors is:

A) Iron
B) Silver
C) Copper
D) Zinc

✅ Answer: C

9. In a DC motor, the commutator:

A) Increases speed
B) Converts DC to AC
C) Reverses current direction
D) Decreases torque

✅ Answer: C

10. A diode allows current to flow in:

A) No direction
B) Both directions
C) Only forward direction
D) Only reverse direction

✅ Answer: C

11. The ideal voltage source has:

A) Zero voltage
B) Infinite resistance
C) Zero internal resistance
D) Very high current

✅ Answer: C

12. The main function of a circuit breaker is to:

A) Increase voltage
B) Regulate frequency
C) Protect circuit from overload
D) Act as a switch

✅ Answer: C

13. Which instrument is used to measure current?

A) Voltmeter
B) Ammeter
C) Wattmeter
D) Ohmmeter

✅ Answer: B

14. An inductor stores energy in the form of:

A) Heat
B) Magnetic field
C) Electric field
D) Light

✅ Answer: B

15. Which law is used to determine the direction of induced current?

A) Faraday’s Law
B) Ohm’s Law
C) Lenz’s Law
D) Gauss’s Law

✅ Answer: C

16. RMS value of AC current is:

A) Maximum value × 0.5
B) Average value × 1.11
C) Peak value / √2
D) Peak value × √2

✅ Answer: C

17. Which device converts AC to DC?

A) Inverter
B) Rectifier
C) Transformer
D) Chopper

✅ Answer: B

18. A synchronous motor runs at:

A) Below synchronous speed
B) Varying speed
C) Synchronous speed
D) Above synchronous speed

✅ Answer: C

19. A fuse works on the principle of:

A) Magnetic effect
B) Electrostatic effect
C) Heating effect
D) Inductive effect

✅ Answer: C

20. The color code for a 1 kΩ resistor with 5% tolerance is:

A) Brown-Black-Red-Gold
B) Red-Black-Red-Silver
C) Orange-Orange-Brown-Gold
D) Brown-Black-Orange-Gold

✅ Answer: A

Conclusion

These questions are excellent for interviews, competitive exams, and foundational understanding. Make sure to regularly practice MCQs to strengthen your concepts and spot knowledge gaps.

👉 Want more MCQs on advanced topics or explanations for each answer? Let me know!