Question

a north pole of strength π A m,is moved around a circle of radius 10cm which lies ​around a long straight conductor carrying a current of 10 A .the work done is nearly

Answer 1

Answer:

Pole strength of the conductor, m = π Am

Current, I = 10 A  

µo = 4 π * 10⁻⁷ H/m

Since a single conductor rotates to make a circular loop of radius 10 cm, therefore, the no. of turns “n” = 1.

We know, the work done is given by,

W = µo * m * n * I

⇒ W = 4 π * 10⁻⁷ * π * 1 * 10

⇒ W = 4* (3.14)² * 10⁻⁷⁺¹ * 1

⇒ W = 39.438 * 10⁻⁶ J ≈ 40 µJ

Hence, the work done is nearly 40 µJ.