A. 730 r.p.m.
B. 960 r.p.m.
C. 1440 r.p.m.
D. 2880 r.p.m.
Related Mcqs:
- A 3-phase 440 V, 50 Hz induction motor has 4% slip. The frequency of rotor e.m.f. will be____________?
A. 200 Hz
B. 50 Hz
C. 2 Hz
D. 0.2 Hz - 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 three-phase induction motors sometimes copper bars are placed deep in the rotor to___________?
A. improve starting torque
B. reduce copper losses
C. improve efficiency
D. improve power factor - In case of 3-phase induction motors, plugging means__________?
A. pulling the motor directly on line without a starter
B. locking of rotor due to harmonics
C. starting the motor on load which is more than the rated load
D. interchanging two supply phases for quick stopping - A 3-phase induction motor stator delta connected, is carrying full load and one of its fuses blows out. Then the motor_______________?
A. will continue running burning its one phase
B. will continue running burning its two phases
C. will stop and carry heavy current causing permanent damage to its winding
D. will continue running without any harm to the winding - A 3-phase induction motor delta connected is carrying too heavy load and one of its fuses blows out. Then the motor______________?
A. will continue running burning its one phase
B. will continue running burning its two phase
C. will stop and carry heavy current causing permanent damage to its winding
D. will continue running without any harm to the winding - The starting torque of a 3-phase squirrel cage induction motor is____________?
A. twice the full load torque
B. 1.5 times the full load torque
C. equal to full load torque - The torque developed by a 3-phase induction motor least depends on__________?
A. rotor current
B. rotor power factor
C. rotor e.m.f.
D. shaft diameter - Temperature of the stator winding of a three phase induction motor is obtained by___________?
A. resistance rise method
B. thermometer method
C. embedded temperature method
D. all above methods - 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