The power input to a 415 V, 50 Hz, 6 pole, 3-phase induction motor running at 975 rpm is 40 kW. If startor losses are 1 kW and friction and windage losses total 2 kW, then efficiency of the motor is

The power input to a 415 V, 50 Hz, 6 pole, 3-phase induction motor run

1.	The power input to a 415 V, 50 Hz, 6 pole, 3-phase induction motor running at 975 rpm is 40 kW. If startor losses are 1 kW and friction and windage losses total 2 kW, then efficiency of the motor is
A.	92.5%
B.	91%
C.	90%
D.	88%
Answer» B. 91%

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The power input to a 415 V, 50 Hz, 6 pole, 3-phase induction motor running at 975 rpm is 40 kW. If startor losses are 1 kW and friction and windage losses total 2 kW, then efficiency of the motor is

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