Question

A coil of 300 turns is wound on a non-magnetic core having a mean circumference of 300 mm and a cross sectional area of 300 mm^2. The inductor of the coil corresponding to a magnetizing electric current of 3 A will be?

(a) 37.68 μH

(b) 47.68 μH

(c) 113.04 μH

(d) 120.58 μH

The question was asked in an interview.

I would like to ask this question from Advanced Problems on Millman’s Theorem and Maximum Power Transfer Theorem in chapter Useful Theorems in Circuit Analysis of Network Theory

Answer 1

The correct choice is (c) 113.04 μH

The explanation: Inductance of the coil, L = \(\frac{μ_0 n^2 A}{l}\)

= \(\frac{4π X 10^{-7}  X 300 X 300 X 300 X 10^{-6}}{300 X 10^{-3}}\)

= 113.04 μH.