Question

A 400/200V transformer has total resistance of 0.04 p.u on its L.V side. This resistance when referred to H.V side would be?

(a) 0.04

(b) 0.02

(c) 0.01

(d) 0.08

This question was posed to me in an online quiz.

This intriguing question originated from Transformer Phasor Diagram in portion Transformers of Electrical Machines

Answer 1

Correct answer is (a) 0.04

To elaborate: The per unit value does not change from the winding side of a transformer.