Hi friends, this post is about induction motor objectives. These are some of the questions asked in previous question papers of Gate, IES and other competitive exams. check out and comment if you have any doubts.....
1) In which of the following tests to be conducted on induction motors, reduced voltage is applied
A) Blocked rotor test
B) No-load test
C) Both (a) and (b)
D) none of these
Ans:A
2) Blocked rotor test of an induction motor corresponds, in case of transformer, to
A) full load
B) half full load
C) no load
D) short circuit operation
Ans:D
3) Circle diagram is employed to determine the performance of a/an
A) synchronous motor
B) induction motor
C) dc motor
D) transformer
Ans:B
4) The core losses, and friction and windage losses in case of an induction motor are determined from the .............. test
A) no-load
B) blocked rotor
C) load
D) stator resistance
Ans:A
5) Short-circuit test is performed on an induction motor to determine
A) short-circuit current under rated voltage
B) equivalent resistance and reactance
C) transformation ratio
D) power factor on short circuit
E) all of the above
Ans:E
6) What is the shunt resistance component in equivalent circuit obtained by no load test of an induction motor representative of?
A) windage and frictional losses only
B) core losses only
C) core,windage and frictional losses
D) copper losses
Ans:B
7) If the rotor power factor of a 3-phase induction motor is 0.866, the spatial displacement between the stator magnetic field and the rotor magnetic field will be
A) 30 degrees
B) 90 degrees
C) 120 degrees
D) 150 degrees
Ans:C
8) The stator of a 6-pole, 3-phase induction motor is fed from a 3-phase 50 Hz supply which contains a pronounced fifth time harmonic. The speed of the fifth space harmonic field produced by the fifth time harmonic in the stator supply will be
A) 200 rpm
B) 1500 rpm
C) 1000 rpm
D) 5000 rpm
Ans:D
9) Crawling of induction motor occurs due to
A) harmonic synchronous torques
B) harmonic induction torques
C) vibration torques
D) both (a) and (b)
Ans:D
10) The cogging occurs in induction motors due to
A) harmonic induction torques
B) harmonic synchronous torques
C) vibration torques
D) both (a) and (b)
Ans:B
If you like my post share it with your friends and subscribe for latest updates..
1) In which of the following tests to be conducted on induction motors, reduced voltage is applied
A) Blocked rotor test
B) No-load test
C) Both (a) and (b)
D) none of these
Ans:A
2) Blocked rotor test of an induction motor corresponds, in case of transformer, to
A) full load
B) half full load
C) no load
D) short circuit operation
Ans:D
3) Circle diagram is employed to determine the performance of a/an
A) synchronous motor
B) induction motor
C) dc motor
D) transformer
Ans:B
4) The core losses, and friction and windage losses in case of an induction motor are determined from the .............. test
A) no-load
B) blocked rotor
C) load
D) stator resistance
Ans:A
5) Short-circuit test is performed on an induction motor to determine
A) short-circuit current under rated voltage
B) equivalent resistance and reactance
C) transformation ratio
D) power factor on short circuit
E) all of the above
Ans:E
6) What is the shunt resistance component in equivalent circuit obtained by no load test of an induction motor representative of?
A) windage and frictional losses only
B) core losses only
C) core,windage and frictional losses
D) copper losses
Ans:B
7) If the rotor power factor of a 3-phase induction motor is 0.866, the spatial displacement between the stator magnetic field and the rotor magnetic field will be
A) 30 degrees
B) 90 degrees
C) 120 degrees
D) 150 degrees
Ans:C
8) The stator of a 6-pole, 3-phase induction motor is fed from a 3-phase 50 Hz supply which contains a pronounced fifth time harmonic. The speed of the fifth space harmonic field produced by the fifth time harmonic in the stator supply will be
A) 200 rpm
B) 1500 rpm
C) 1000 rpm
D) 5000 rpm
Ans:D
9) Crawling of induction motor occurs due to
A) harmonic synchronous torques
B) harmonic induction torques
C) vibration torques
D) both (a) and (b)
Ans:D
10) The cogging occurs in induction motors due to
A) harmonic induction torques
B) harmonic synchronous torques
C) vibration torques
D) both (a) and (b)
Ans:B
If you like my post share it with your friends and subscribe for latest updates..
EmoticonEmoticon