A 3 phase induction motor is controlled by voltage and frequency contr – McqOptions

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1.	A 3 phase induction motor is controlled by voltage and frequency control such that the ratio V/f is constant. At 50 Hz, the speed is 1440 rpm. At 25 Hz, the speed is likely to be
A.	about 1350 rpm
B.	about 720 rpm
C.	about 360 rpm
D.	either (b) or (c)
Answer» C. about 360 rpm

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