Q.1
In squirrel cage induction motors, the rotor slots are usually given slight skew in order to
Q.2
If an induction motor with certain ratio of rotor to stator slots, runs at 1/7 of the normal speed, the phenomenon will be termed as
Q.3
The 'cogging' of an induction motor can be avoided by
Q.4
In three-phase induction motors sometimes copper bars are placed deep in the rotor to
Q.5
The speed characteristics of an induction motor closely resemble the speed-load characteristics of which of the following machines
Q.6
For driving high inertia loads best type of induction motor suggested is
Q.7
An induction motor is
Q.8
Lubricant used for ball bearing is usually
Q.9
For which motor the speed can be controlled from rotor side?
Q.10
Step-less speed control of induction motor is possible by which of the following methods?
Q.11
The starting torque of a 3 phase squirrel cage induction motor is
Q.12
A pump induction motor is switched on to a supply 30% lower than its rated voltage. The pump runs. What will eventually happen? It will
Q.13
The circle diagram for an induction motor cannot be used to determine
Q.14
A 500 kW, 3-phase, 440 volts, 50 Hz, A.C. induction motor has a speed of 960 r.p.m. on full load. The machine has 6-poles. The slip of the machine will be
Q.15
It is advisable to avoid line starting of induction motor and use starter because
Q.16
A double squirrel-cage induction motor has
Q.17
The term 'cogging' is associated with
Q.18
Which is of the following data is required to draw the circle diagram for an induction motor?
Q.19
The low power factor of induction motor is due to
Q.20
The injected e.m.f. in the rotor of induction motor must have
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