Construction & Working Principle
Applications
Characteristics
Numerical Type
Identification
100

An induction motor can be said analogous to

Transformer

100

Wound rotor induction motor is most appropriate for the applications requiring____________ starting torque.

Variable

100

A 3-phase induction motor is operating at slip ā€˜sā€™. If the slip is reversed, its slip at the instant will be ______

2-s

100

A 50 Hz, 3-phase induction motor has a full load speed of 1440 r.p.m. The number of poles in the motor is

4

100

The below diagram belongs to which motor?

Split-Phase Induction Motor

200

Slip rings are usually made of

Phosphor bronze

200

The torque in an induction motor varies as _______ of the voltage.

Square

200

In a three-phase induction motor, the starting torque is maximum when?

R2 = X2

200

For a 4 pole three phase induction motor having synchronous speed of 1500 rpm is operating at 1450rpm. The frequency of the induced emf in rotor is?

100Hz

200

Torque-speed Characteristics belongs to which motor?

Split-Phase Induction Motor

300

The direction/speed of RMF when a three phase supply is given to stator of three phase induction motor is

Synchronous Speed

300

A shaded Pole induction motor can be used for

Toys, Hair dryers, calculators, Photo Copying machine, record players.

300

In an induction motor, what is the ratio of the rotor copper loss to rotor input?

slip

300

For a 4-pole, 3-phase induction motor the rotor speed found is 2100 rpm at 50 Hz. Then the phase sequence of the emf generated will be?

acb

300

In below Circle Diagram AD represents


Torque Line

400

Two three phase induction motors A and B are identical in all respects except that motor A has a larger air-gap than motor B. Which motor will have poorer power factor?

A

400

Split-Phase Induction motors are available in the range of

1/20 to 1/2 KW

400

 An induction motor X operating at the slip of 3%. An induction motor Y operating at slip of 40%. 

Which motor is stable?

X

400

A three phase, 50 Hz induction motor has a full load speed of 1440 rpm. Speed of the stator filed with respect to stator structure is?(In rad/sec)

157 rad/sec

400

In below Circle Diagram CD represents


Rotor Cu Loss

500

How a three phase induction motor operates when rotor frequency is equal to stator frequency?

It will not operate

500

Capacitor start induction motors are having _______ starting torque.

High

500

At standstill the equivalent of the 3-phase induction motor is similar to

Short-circuited two winding transformer

500

In a three phase induction motor, voltage between the slip rings at standstill is 50 V. At full load the slip is 0.04. The voltage between slip rings at full load is?

2V

500

The torque slip characteristic of the induction motor is

Identify the slip region.

Low Slip Region