Question
a.
about 1350 rpm
b.
about 720 rpm
c.
about 360 rpm
d.
either (b) or (c)
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Q. 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
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