INDUCTION MOTOR

a rotating magnetic field is created by :

• applying three phase waveforms to rotor winding placed 120 degrees apart.

• applying three phase line voltages to stator winding via sliprings

• applying three phase line voltages to red yellow and blue stator windings.

• applying three phase phase voltages to a delta connected load.

a cage rotor consists of

• laminated soft iron with copper or iron end rings

• laminated soft iron core containing longitudinal copper or iron bars which are capped at each end via a shorting plate.

• laminated silica steel core containing longitudinal copper bars shorted at one end only

• laminated soft iron core with three phase star connected windings and slip rings,

rotor eddy currents are :-

• large currents created in the laminated iron core .

• large currents induced in copper or iron bars that are shorted at each end

• currents caused by hysteresis loops in soft iron

• found in ox bow lakes

slip is defined as :

• the difference between synchronous speed and rotor speed

• the difference between rotor speed and synchronous speed

• synchronous speed - rotor speed / rotor speed

• (rotor speed - synchronous speed ) / synchronous speed

the rotor in an induction motor can :-

• reach synchronous speed quickly

• reach rotor speed slowly

• always rotate close to the synchronous speed

• can never reach synchronous speed

rotation is produced in a rotor due to :

• Flemings left hand rule

• Flemings right hand rule

• Faradays laws of mutual induction

• Lenzes Law

The rotating part of a motor is

• Stator

• Rotor

• Frame

• Bearing

3-phase voltage supply given to ___________ of 3 phase Induction Motor

• Stator
• rotor
• Laminations
• None of the above

If slip value is less than 1, it means, the machine is

• motoring

• Braking

• Generating

• Transferring

What creates a rotating magnetic field in an induction motor?

• The angular speed of the motor

• Three phase current flowing in the rotor

• Three phase current flowing in the stator

• A single phase current flowing in both the rotor and the stator