Electrical Engineering MCQs
Electrical Engineering MCQs are essential for aspirants preparing for engineering exams and job tests conducted by PPSC, FPSC, NTS, and other testing services. This section includes questions from power systems, basic electronics, circuit analysis, machines, measurements, and electromagnetism. Whether you're revising for an academic test or preparing for professional assessments, these multiple-choice questions are tailored to cover the entire Electrical Engineering syllabus. The content is designed to reflect current trends in competitive exams and industry requirements. Practicing these MCQs will help you strengthen your concepts, improve time management, and increase your chances of scoring high in electrical engineering exams in Pakistan.
Q: Transistor is used as a
A) Filter
B) Switch or amplifier
C) Rectifier
D) Sensor
✅ Correct Answer: B
Explanation: Transistors are fundamental components in switching and amplification.
Q: Electrolysis is a process related to
A) Thermal conduction
B) Magnetism
C) Electrical conduction
D) Chemical decomposition
✅ Correct Answer: D
Explanation: Electrolysis decomposes compounds using electricity.
Q: In star connection, line voltage is
A) 3 × phase voltage
B) √3 × phase voltage
C) Half phase voltage
D) Equal to phase voltage
✅ Correct Answer: B
Explanation: In a star connection, line voltage = √3 × phase voltage.
Q: An ideal voltage source has
A) High resistance
B) Zero voltage
C) Infinite current
D) Zero resistance
✅ Correct Answer: D
Explanation: Ideal voltage sources have zero internal resistance.
Q: Power in a three-phase system is calculated using
A) P = I^2 × R
B) P = √3 × VL × IL × pf
C) P = V × pf
D) P = VL × IL
✅ Correct Answer: B
Explanation: Total power in 3-phase systems is calculated with the given formula.
Q: The skin effect in conductors increases with
A) Higher frequencies
B) Lower frequencies
C) Zero voltage
D) Larger resistance
✅ Correct Answer: A
Explanation: At high frequencies, current flows near the conductor’s surface.
Q: An oscilloscope is used to measure
A) Frequency
B) Voltage and waveform
C) Current only
D) Temperature
✅ Correct Answer: B
Explanation: Oscilloscopes visualize and measure electrical waveforms.
Q: The purpose of using a relay in circuits is to
A) Protect against overvoltage
B) Amplify current
C) Store charge
D) Switch circuits remotely
✅ Correct Answer: D
Explanation: Relays switch electrical circuits mechanically or electronically.
Q: When a circuit is open, the current is
A) Moderate
B) Zero
C) Infinite
D) Maximum
✅ Correct Answer: B
Explanation: An open circuit means a break, so no current flows.
Q: The instrument for measuring very small currents is
A) Voltmeter
B) Wattmeter
C) Galvanometer
D) Ammeter
✅ Correct Answer: C
Explanation: Galvanometers detect and measure small electric currents.