Why motor starting current is high?

During starting of the motor the slip of the motor is very less i.e
Slip=Synchronous speed(Ns)-speed of the                 rotor(Nr)
As the rotor is stable during starting ,the no of magnetic flux (which is created by the stator) cut by the rotor is very high, hence high starting current. Once the rotor start rotating the slip of the motor decrease i.e no of flux cut by stator decreases and hence the current.

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