A shunt DC motor rated at 230 V, with armature resistance of 0.05 22 and field resistance of 75 12, consumes 7 A when no-load at 1120 rpm. The current consumed by the motor at another given load is 46 A. Find (a) motor speed a the given load, (b) rotational and core losses, and (c) efficiency. Answer: (a) 1110.5 rpm; (c) 903.9 W; (c) 83.9%;