### MCQs of Induction motor characteristics

Showing 51 to 60 out of 63 Questions
51.

The number of stator poles can be changed by (i) multiple stator winding, (ii) method of consequent poles (iii) pole amplitude modulation

 (a) (i) only (b) (i) and (ii) only (c) (i) and (iii) only (d) (i), (ii) and (iii)
52.

In 3-Φ I.M. for a given torque, slip can be increased by decreasing the rotor resistance.

 (a) True (b) False
53.

In 3-Φ I.M., reduction in the supply voltage will reduce the motor torque

 (a) True (b) False
54.

Induction motor is not much used as generator because it require/s more

 (a) reactive power for its operation (b) active power for its operation (c) active and reactive power for its operation (d) none of these
55.

Which of the following is not the mode in the Torque Slip Characteristics of Three Phase I.M

 (a) Braking Mode (b) Generating mode (c) Motoring mode (d) Reverse Braking
56.

If the rotor resistance of an induction motor is doubled, keeping the other parameters constant, then the maximum torque of the induction motor will become

 (a) Double (b) Halved (c) One fourth (d) Remains same
57.

The value of slip for motoring, generating and braking region respectively are

 (a) s > 1, 0 < s < 1, s < 0 (b) s < 0, 0 < s < 1, s > 1 (c) 0 < s < 1, s > 1, s < 1 (d) 0 < s < 1, s < 0, s > 1
58.

The curve obtained by plotting torque against slip from s=1 to s=0 is called torque slip characteristics. The nature of the graph in the low slip region and in the high slip region is

 (a) Rising exponential, decaying exponential (b) Both will be straight line (c) Straight line, rectangular parabola (d) Straight line, decaying exponential
59.

For maximum torque, the only parameter which controls the torque is slip. The maximum torque is

 (a) directly proportional to the rotor resistance (b) inversely proportional to the rotor resistance (c) directly proportional to the slip times the rotor resistance (d) independent of the rotor resistance
60.

Slip of a induction motor will be zero

 (a) At start (b) When machine is rotating at its maximum speed (c) When it is rotating at half of the maximum speed (d) Cannot be zero
Showing 51 to 60 out of 63 Questions