Electrical Engineering Mcqs Practice Test

Question 1

Application of Norton’s theorem to a circuit yields:________________?

Accepted Answer

A. equivalent current source and impedance in parallel

Question 2

An ideal voltage source has__________?

Accepted Answer

A.  zero internal resistance

Question 3

If the energy is supplied from a source, whose resistance is 1 ohm, to a load of 100 ohms the source will be___________?

Accepted Answer

A.  a voltage source

Question 4

For similar carrier and modulating signals, the line current used in CSI is_____________?

Accepted Answer

A. Identical to line voltage in a VSI

Question 5

During the commutation period in 3 phase converter, overlap time is____________?

Accepted Answer

C. Dependent on both the load current and load voltage behind the short circuit current

Question 6

The effects of EMI can be reduced by_____________?

Accepted Answer

D. All of these

Question 7

An SCR is made up of silicon because_____________?

Accepted Answer

. silicon has small leakage current than germanium

Question 8

AC power in a load can be controlled by using_____________?

Accepted Answer

A. two SCR’s in parallel opposition

Question 9

The switching function of semiconductor devices can be characterized with____________?

Accepted Answer

D. Duty ratio, frequency and time delay

Question 10

Electrical power output in a D.C. generator is equal to_____________?

Accepted Answer

D. Mechanical power input – iron and friction losses – copper losses

Question 11

If a shunt motor is started with its field winding open then___________?

Accepted Answer

C. It will rotate at dangerously high speed

Question 12

The power demand can be estimated approximately by____________?

Accepted Answer

C. Statistical method

Question 13

Power electronics essentially deals with control of a.c. power at____________?

Accepted Answer

D. 50 Hz frequency

Question 14

A synchronous motor can develop synchronous torque:

Accepted Answer

C. only at synchronous speed

Question 15

The maximum power developed in a synchronous motor will depend on__________?

Accepted Answer

D. the rotor excitation, supply voltage and maximum value of coupling angle (90°)

Question 16

In a synchronous motor, the breakdown torque is__________?

Accepted Answer

B. directly proportional to applied voltage

Question 17

A synchronous motor which works on a leading power factor and does not drive a mechanical load is called as_________?

Accepted Answer

C. synchronous condenser

Question 18

If the synchronous motor, properly synchronised to the supply is running on no load and is having negligible loss then_____________?

Accepted Answer

A. the stator current will be zero

Question 19

The coupling angle or load angle of synchronous motor is defined as the angle between the__________?

Accepted Answer

B. rotor and the stator poles of opposite polarity

Question 20

The maximum torque which a synchronous motor will develop at rest for any angular position of the rotor, at rated stator supply voltage and frequency, is known as__________?

Accepted Answer

A. locked-rotor torque