Utilization of Electrical Energy past question

A DC chopper fed from 400V supply runs a separately excited motor. The armature resistance Ra = 0.1 Ω. The motor voltage constant is 4 Vsec/radian, the average armature current Ia = 150 A. the armature current is continuous and has negligible ripple. Determine (a) The input power (b) The motor speed and (c) The developed torque for a duty cycle of 60%. Neglect the losses in chopper. If the duty cycle of chopper varies between 10% and 90%, find maximum and minimum speed.