Answer / harshid agrawal

because at the starts dc motor do not have the back emf and due to that applied voltage is not oppose by back emf and winding have small amount of resistance so according to ohm's law current increse to 50-60% of it's rated current.
and in case of ac motor as the at the start there is no any rotation of the rotor wrt stator winding and the emf induced in the rotor winding depens upon the flux link with it and it's relative speed as the we apply full rated voltage at first it cause max flux link with rotor as it remain stationary and max emf induce in rotor winding as rotor winding is short circuited in induction motor it cause high flow of current in rotor .
that's bot ac and dc takes high current @ starts

Answer / nizamudeen

1 back emf is zero
2 winding resistance is lass

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