Why th shaft speed of an induction motor has to be lower tha

Why th shaft speed of an induction motor has to be lower than synchronous speed in practical applications

Solution

if the shaft speed or rotor speed of an induction motor are equal to the synchronous speed then the relative speed becomes zero in other words the slip becomes zero so there would be no flux cutting action in induction motor and therefore no emf will induced in the rotor so the induction motor will stop operating gradually. incase if the if the shaft speed is greater than the synchronous speed then the induction motor acts like a induction generator with a negative slip.