If a machine has P poles and the armature rotates at N revolutions per – McqOptions

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1.	If a machine has P poles and the armature rotates at N revolutions per minute, then the frequency of induced emf in the armature winding of the machine is:
A.	\(f = \frac{{50}}{{PN}}Hz\)
B.	\(f = \frac{{120}}{{PN}}Hz\)
C.	\(f = \frac{{PN}}{{120}}Hz\)
D.	\(f = \frac{{PN}}{{50}}Hz\)
Answer» D. \(f = \frac{{PN}}{{50}}Hz\)

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