Question

The unit for permeability of free space is?

(a) Henry

(b) Henry-m

(c) Henry/m

(d) Henry/m^2

I have been asked this question in a job interview.

This intriguing question originated from Permeability of Free Space or Magnetic Constant topic in division Simple Magnetic Circuits of Basic Electrical Engineering

Answer 1

Right option is (c) Henry/m

For explanation I would say: Using formula of self inductance of solenoid, L=µ0n^2A/l

We get unit of µ0 = Henry/m.