Top 250+ Solved Electrical and Electronics Engineering MCQ Questions Answer
Q. The operation of an induction motor is based on
a. len\s law
b. ampere law
c. principle of mutual induction
d. principle of self induction
Q. The rotating magnetic field produced by stator currents rotates at
a. synchronous speed , ns
b. rotor speed n
c. speed = ns - n
d. a speed higher than synchronous speed
Q. The relative speed between stator flux and rotor is equal to
a. synchronous speed , ns
b. rotor speed n
c. zero
d. ns - n
Q. Two of the supply terminals to a 3-phase induction motor get interchanged during reconnection after normal maintenance. When switched on to supply, the motor will
a. rotate in the same direction as before maintenance.
b. rotate in a direction opposite to that before maintenance.
c. not start at all.
d. get heated and damage
Q. The direction of rotation of a 3-phase induction motor can be reversed by
a. interchanging any two leads from supply.
b. interchanging any two leads from slip-rings.
c. interchanging all the three leads from the supply
d. disconnecting any one phase
Q. The speed of rotor of an induction motor is always ………………… synchronous speed.
a. equal to
b. more than
c. less than
d. half of
Q. Synchronous speed is defined as the speed at which the
a. stator magnetic field rotates.
b. rotor rotates on no-load.
c. rotor rotates on full load.
d. none of the above.
Q. The speed of rotating field due to rotor currents relative to rotor surface in an induction motor is
a. n
b. s.n
c. ns
d. s.ns