Question

What is the formula for the area of the ring?

(a) area of the ring = depth of the end ring + thickness of the end ring

(b) area of the ring = depth of the end ring – thickness of the end ring

(c) area of the ring = depth of the end ring / thickness of the end ring

(d) area of the ring = depth of the end ring * thickness of the end ring

I have been asked this question by my college professor while I was bunking the class.

Question is taken from Design of End Rings topic in division Three Phase Induction Motor of Design of Electrical Machines

Answer 1

Right option is (d) area of the ring = depth of the end ring * thickness of the end ring

The best explanation: For calculation of the area of end rings, first the depth of end rings is calculated. Next, the thickness of the end ring is calculated and substituting in the above formula gives the area of the ring.