Question:

Load torques can be classified into how many types?

A.

Three

B.

Two

C.

Four

D.

Five

Answer» b. Two

Question:

Effect of friction torque is more pronounced

A.

when the drive is running on full speed

B.

when the drive is being started

C.

when the drive is being stopped

D.

when the drive at half of its normal speed.

Answer» b. when the drive is being started

Question:

Torque inversely varies with the speed in the windage load torque component.

A.

True

B.

False

C.

none

D.

all

Answer» b. False

Question:

Rolling mills exhibit what type of load torque characteristics?

A.

Constant torque characteristics

B.

Linearly rising torque characteristics

C.

Non-Linearly rising torque characteristics

D.

Non-Linearly decreasing torque characteristics

Answer» d. Non-Linearly decreasing torque characteristics

Question:

Type-A chopper is used for obtaining which type of mode?

A.

Motoring mode

B.

Regenerative braking mode

C.

Reverse motoring mode

D.

Reverse regenerative braking mode

Answer» a. Motoring mode

Question:

A motor of less than full load power rating can be used if the load is

A.

continuous duty

B.

short time duty

C.

intermittent periodic duty

D.

none of these.

Answer» b. short time duty

Question:

To save the energy during braking

A.

dynamic braking is used

B.

plugging is used

C.

regenerative braking is used

D.

mechanical braking is used.

Answer» c. regenerative braking is used

Question:

Rotor resistance speed control is used in

A.

squirrel cage induction motor

B.

synchronous motor

C.

slip ring induction motor

D.

dc shunt motor.

Answer» c. slip ring induction motor

Question:

Boost converter is used to _________

A.

Step down the voltage

B.

Step up the voltage

C.

Equalize the voltage

D.

Step up and step down the voltage

Answer» b. Step up the voltage

Question:

Most commonly used ac motor is

A.

Synchronous motor

B.

Slip ring induction motor

C.

Squirrel cage induction motor

D.

ac commutator induction motor.

Answer» c. Squirrel cage induction motor