why does a polyphase motor start without special starting wi

why does a polyphase motor start without special starting windings?

Solution

Ans) The poly phase motor start without a special winding because in poly phase motors,the magnetic field produed is rotating in nature called Rotating magnetic field RMF,which causes the motor to rotate without the need of starting winding ,where as in signle phase motors ,magnetic field produced is in alternating in nature,produces alternating torque whose average is zero ,hence it cannot start on its own ,so in this case special windings are needed