Explore topic-wise MCQs in Alternating Current and Voltage .

This section includes 8 Mcqs, each offering curated multiple-choice questions to sharpen your Alternating Current and Voltage knowledge and support exam preparation. Choose a topic below to get started.

1.

In a Y-connected source feeding a -connected load,

A. each phase of the load has one-third of the full line voltage across it
B. each phase of the load has two-thirds of the full line voltage across it
C. each phase of the load has the full line voltage across it
D. each phase of the load has a voltage across it equal to
Answer» D. each phase of the load has a voltage across it equal to
Discussion
2.

The most common type of ac motor is the

A. single-phase induction motor
B. two-phase induction motor
C. three-phase induction motor
D. two-phase squirrel-cage motor
Answer» D. two-phase squirrel-cage motor
Discussion
3.

A three-phase -connected generator is driving a balanced load such that each phase current is 12 A in magnitude. When I ? a = 12 30° A, what are the polar expressions for the other phase currents?

A. I ? b = 12 150° A, I ? c = 12 –90° A
B. I ? b = 12 120° A, I ? c = 12 30° A
C. I ? b = 12 30° A, I ? c = 12 120° A
D. I ? b = 12 90° A, I ? c = 12 90° A
Answer» B. I ? b = 12 120° A, I ? c = 12 30° A
Discussion
4.

If in a Y-connected ac generator, each phase voltage has a magnitude of 90 V RMS , what is the magnitude of each line voltage?

A. 0 V
B. 90 V
C. 156 V
D. 180 V
Answer» D. 180 V
Discussion
5.

A three-phase generator is connected to three 90 load resistors. Each coil generates 120 V ac. A common neutral line exists. How much current flows through the common neutral line?

A. 0 A
B. 1.33 A
C. 3.99 A
D. 2.66 A
Answer» B. 1.33 A
Discussion
6.

A single-phase sinusoidal voltage of 120 V is connected to a 90 load. Current in the circuit is

A. 13.3 mA
B. 133 mA
C. 1.33 A
D. 6.2 A
Answer» D. 6.2 A
Discussion
7.

A two-phase generator is connected to two 90 load resistors. Each coil generates 120 V ac. A common neutral line exists. How much current flows through the common neutral line?

A. 1.33 A
B. 1.88 A
C. 2.66 A
D. 1.77 A
Answer» E.
Discussion
8.

A constant load power means a uniform conversion of

A. mechanical to electrical energy
B. electrical to mechanical energy
C. current to voltage
D. voltage to current
Answer» C. current to voltage
Discussion