Question

If induction motor air gap power is 2 KW and mechanically developed power is 1 KW, then rotor ohmic loss will be _________ KW.

(a) 1

(b) 2

(c) 3

(d) 4

I got this question during an online exam.

The query is from Induction Motors topic in chapter Speed Control of Direct Current Motors & Induction Motors of Electric Drives

Answer 1

Right answer is (a) 1

To explain I would say: Rotor ohmic losses are due to the resistance of armature windings. Net input power to the rotor is equal to the sum of rotor ohmic losses and mechanically developed power. Rotor ohmic losses=Air gap power-Mechanical developed power=2-1=1 KW.