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What is the frequency of a 3-phase induction motor if has 12 poles and its synchronous speed is 620 rpm?

What is the frequency of a 3-phase induction motor if has 12 poles and its synchronous speed is 620 rpm? Correct Answer 62 Hz

GiveNumber of poles of motor(P)=12 Synchronous speed(Ns) = 620 rpm Synchronous speed(Ns) = 120f/P Frequency (f)=(Ns*P)/120 Frequency(f)=62 Hz.

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