Basic Electrical Engineering MCQs (Part-4)

What happens to the current in a circuit if the resistance is doubled while the voltage remains constant?

A Current doubles
B Current remains the same
C Current is halved
D Current becomes zero

Which device is used to step up or step down AC voltage?

A Generator
B Transformer
C Rectifier
D Motor

What is the function of an Earth Leakage Circuit Breaker (ELCB)?

A To prevent overcurrent
B To detect ground faults
C To control voltage fluctuations
D To reduce resistance

In a capacitor, the energy is stored in:

A Magnetic field
B Electric field
C Resistance
D Inductance

Which law states that the total current entering a junction equals the total current leaving it?

A Ohm’s Law
B Kirchhoff’s Current Law
C Faraday’s Law
D Lenz’s Law

What is the primary purpose of a fuse in an electrical circuit?

A To measure current
B To regulate voltage
C To protect against overcurrent
D To store energy

What does an oscilloscope measure?

A Resistance
B Voltage over time
C Capacitance
D Magnetic field

What is the purpose of a commutator in a DC motor?

A To generate power
B To reverse the direction of current
C To reduce resistance
D To step up voltage

What is the unit of electric power?

A Joule
B Watt
C Volt
D Ampere

What is the main difference between a series circuit and a parallel circuit?

A Current is the same in all components of a series circuit
B Voltage is the same in all components of a series circuit
C Current is different in all components of a series circuit
D Voltage is different in all components of a parallel circuit

What type of current does a battery produce?

A Alternating Current (AC)
B Direct Current (DC)
C Pulsating Current
D No current

Which of the following is an ohmic conductor?

A Semiconductor
B Filament lamp
C Copper wire
D Diode

What is the main disadvantage of an open circuit?

A Infinite resistance
B No current flow
C High power consumption
D Overcurrent

Which instrument is used to measure very high resistances?

A Ammeter
B Megger
C Voltmeter
D Multimeter

What is the primary role of an electric motor?

A To convert electrical energy into mechanical energy
B To convert mechanical energy into electrical energy
C To store energy
D To regulate voltage

Which phenomenon is responsible for the working of an electric bell?

A Capacitance
B Electromagnetism
C Inductance
D Thermal effect

What happens to the brightness of a bulb if its filament resistance increases?

A Brightness increases
B Brightness decreases
C Brightness remains the same
D The bulb explodes

What is the function of a rectifier in an electrical circuit?

A To amplify voltage
B To convert AC to DC
C To store charge
D To decrease resistance

What causes a thermal effect in electrical circuits?

A Inductance
B Resistance
C Capacitance
D Voltage drop

What is the standard frequency of AC supply in India?

A 50 Hz
B 60 Hz
C 100 Hz
D 25 Hz