THREE PHASE INDUCTION MOTORS QUIZ

If the rotor slots are made deeper, rotor resistance is ______

Decreased at starting

Increased at starting

Increased under running conditions

None of the listed here

TRUE ANSWER : ?
YOUR ANSWER : ?

The induction motor has lagging power factor during

None of the listed here

Starting only

Operation only

Both starting and operation

TRUE ANSWER : ?
YOUR ANSWER : ?

The torque developed by a 3 phase induction motor least depends on

Rotor current

Rotor power factor

Rotor emf

Shaft diameter

TRUE ANSWER : ?
YOUR ANSWER : ?

The shape of the torque/slip curve of induction motor is

Hyperbola

Straight line

Parabola

Rectangular parabola

TRUE ANSWER : ?
YOUR ANSWER : ?

The number of slip rings on a squirrel cage induction motor is usually

Three

Two

One

None

TRUE ANSWER : ?
YOUR ANSWER : ?

The synchronous speed of a 3-phase induction motor having 20 poles and connected to a 50 Hz source is _____

1200 rpm

1000 rpm

600 rpm

300 rpm

TRUE ANSWER : ?
YOUR ANSWER : ?

The rotor of an induction motor runs at

Below synchronous speed

Any of the above

Synchronous speed

Above synchronous speed

TRUE ANSWER : ?
YOUR ANSWER : ?

Very large 3-phase induction motors (greater than 25 HP) are started _____

Star-delta starting

By auto transformer starting

Direct on line

None of the listed here

TRUE ANSWER : ?
YOUR ANSWER : ?

The shaft of induction motor is made of

Any of the listed here

Flexible

Stiff

Hollow

TRUE ANSWER : ?
YOUR ANSWER : ?

The term cogging is associated with

Compound generators

Induction motors

Dc series motors

Three phase transformer

TRUE ANSWER : ?
YOUR ANSWER : ?

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