AC 3 PHASE INDUCTION MOTOR - Quiz

1) What is the speed of rotating magnetic field in a 3f induction motor?

Rotor speed Synchronous speed Motor speed Rated speed

2) What is the synchronosis speed of a 3 phase induction motor if the supply frequency is 50 Hz and number of pole is 4?

1400 rpm 1500 rpm 1450 rpm 1000 rpm

3) Which material is used to wound rotor of squirrel cage induction motor?

Aluminium Enamelled copper conductor Silicon steel Copper bars

4) Which part of squirrel cage rotor is short circuited?

End rings Shaft End cover hysteresis Bearings

5) Why the core of 3f induction motor is laminated?

To reduce friction loss To reduce eddy current loss To reduce hysterism loss To reduce starting current