Question

Considering a transformer at no load is excited at rated voltage. A small recognizable gap is made in the yoke of the limbs. With this altercation, the transformer core flux ___________

(a) will decrease and magnetizing current will increase

(b) will remain constant and magnetizing current will increase

(c) as well as magnetizing current will increase

(d) as well as magnetizing current both will decrease

I have been asked this question in homework.

This interesting question is from Transformer Phasor Diagram in chapter Transformers of Electrical Machines

Answer 1

Right choice is (b) will remain constant and magnetizing current will increase

To explain I would say: The reluctance of the path increases here after making the cut. so the magnetizing current will increase but the core flux will be same as it depends on the applied voltage not the reluctance.