Basic Electrical Engineering MCQs (Part-3)

Which component opposes the change in current in a circuit?

A Resistor
B Capacitor
C Inductor
D Diode

What is the relationship between voltage and current in a purely resistive circuit?

A Voltage leads current by 90°
B Voltage lags current by 90°
C Voltage and current are in phase
D Voltage and current are out of phase

Which of the following devices uses the principle of electromagnetic induction?

A Transformer
B Capacitor
C Resistor
D Battery

What is the unit of inductance?

A Farad
B Ohm
C Henry
D Watt

In a series RLC circuit, at resonance, the impedance is:

A Maximum
B Minimum
C Zero
D Infinite

Which electrical symbol represents a resistor in a circuit diagram?

A A zigzag line
B A straight line
C A circle with a cross
D A rectangle

Which of the following determines the polarity of an induced voltage in a conductor?

A Coulomb’s Law
B Faraday’s Law
C Lenz’s Law
D Ohm’s Law

Which safety device detects and interrupts leakage currents to prevent electric shocks?

A Fuse
B Circuit Breaker
C Residual Current Device (RCD)
D Transformer

What is the main purpose of a step-down transformer?

A To increase current
B To reduce voltage
C To decrease power
D To improve resistance

What is the total capacitance when capacitors are connected in series?

A Equal to the sum of individual capacitances
B Less than the smallest capacitance
C Equal to the largest capacitance
D Equal to the product of capacitances

What is the purpose of using a rheostat in a circuit?

A To measure voltage
B To vary resistance
C To amplify current
D To convert AC to DC

What is the main difference between AC and DC?

A AC flows in one direction, while DC reverses direction
B AC reverses direction periodically, while DC flows in one direction
C AC has higher voltage than DC
D DC is safer than AC

Which of the following appliances typically uses a DC motor?

A Ceiling fan
B Vacuum cleaner
C Electric car
D Refrigerator

What is the standard voltage level for residential wiring in most countries?

A 120V or 230V
B 12V or 24V
C 400V or 415V
D 600V or 1000V

Which component converts AC to DC in an electrical circuit?

A Diode
B Transformer
C Resistor
D Capacitor

Which factor affects the resistance of a conductor?

A Length
B Cross-sectional area
C Material
D All of the above

What is the purpose of a multimeter?

A To measure current only
B To measure resistance only
C To measure multiple quantities like voltage, current, and resistance
D To measure temperature

What does the term “short circuit” mean?

A High resistance in the circuit
B A direct connection between two points of different potentials
C No current in the circuit
D A completely open circuit

What is the efficiency of an ideal transformer?

A 0%
B 50%
C 100%
D Infinite

Which device is used to detect the presence of electric fields?

A Voltmeter
B Galvanometer
C Electroscope
D Ammeter