A. high speed steel
B. stainless steel
C. carbon steel
D. cast iron
Related Mcqs:
- Which type of bearing is provided in small induction motors to support the rotor shaft ?
A. Ball bearings
B. Cast iron bearings
C. Bush bearings
D. None of the above - Slip ring motor is preferred over squirrel cage induction motor where___________?
A. high starting torque is required
B. load torque is heavy
C. heavy pull out torque is required
D. all of the above - An induction motor is identical to_________?
A. D.C. compound motor
B. D.C. series motor
C. synchronous motor
D. asynchronous motor - The crawling in the induction motor is caused by____________?
A. low voltage supply
B. high loads
C. harmonics develped in the motor
D. improper design of the machine
E. none of the above - In the circle diagram for induction motor, the diameter of the circle represents____________?
A. slip
B. rotor current
C. running torque
D. line voltage - In a three-phase induction motor, the number of poles in the rotor winding is always__________?
A. zero
B. more than the number of poles in stator
C. less than number of poles in stator
D. equal to number of poles in stator - 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____________?
A. stall after sometime
B. stall immediately
C. continue to run at lower speed without damage
D. get heated and subsequently get damaged - 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__________?
A. 0.01
B. 0.02
C. 0.03
D. 0.04 - In an induction motor if air-gap is increased__________?
A. the power factor will be low
B. windage losses will be more
C. bearing friction will reduce
D. copper loss will reduce In an induction motor - The starting torque of a three phase induction motor can be increased by__________?
A. increasing slip
B. increasing current
C. both A. and (b)
D. none of the above
