Question

How are the air gaps arranged in the flat faced armature type?

(a) magnetic in series and mechanical in parallel

(b) magnetic in series and parallel

(c) mechanical in series and parallel

(d) magnetic in parallel and mechanical in series

This question was addressed to me during a job interview.

Question is taken from Types of Electromagnets topic in division Design of Electromagnets of Design of Electrical Machines

Answer 1

Right option is (a) magnetic in series and mechanical in parallel

The explanation: The flat faced armature types have 2 air gaps within them. They are magnetic in series and are mechanical in parallel and hence produce a holding surface of large effective area.