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a three-phase bipolar motor of 10.72 [HP] has an efficiency of 80% when working at full...

a three-phase bipolar motor of 10.72 [HP] has an efficiency of 80% when working at full load at 2700 (rpm), if it is connected to a network of 440 (V) at 50 [Hz] calculate

a.) The synchronous motor speed in (rpm)
b.) Engine displacement.

c.) rotor frequency at full load.

d.) If the kilowatt hour costs $ 185.39. The money saved in energy consumption if the engine works continuously for three years and is replaced by an engine with 97% efficiency?

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