Question

What is the range of size of the motor (kW) for efficiency nearly equals to 90%?

(a) 15-150

(b) 0-2

(c) 3-15

(d) 150-250

This question was addressed to me by my college director while I was bunking the class.

The query is from Motors Rating and Heating in division Rating and Heating of Motors of Electric Drives

Answer 1

Right choice is (a) 15-150

For explanation I would say: As the size of the motor increases its speed decreases. The range of size of the motor (kW) for efficiency nearly equals to 90 % is 15-150. The efficiency increases as the size increases.