why the starting torque is high in dc series motor..

Answer Posted / naveen

Torque is proportional to flux and current.

reason why starting torque is high in series motor only is:
in DC series motor, flux is also proportional to current since the field winding is series with DC motor.

and the reason why its high in start is :
in starting back emf is 0 . current=(V-Ef)/R when Ef is 0 current attains high value which decreases as the speed of motor increases and thus the Ef.

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