Moving Charges and Magnetism – Solutions

1) A circular coil of wire consisting of 100 turns, each of radius 8.0 cm carries a current of 0.40 A. what is the magnitude of the magnetic field B at the centre of the coil?

Solution:

By definition, B = μ₀/4π(2πnl/r)

Where  = absolute permeability of the medium

N = no. of turns

I = current

r = radius of coil

While substituting the values:

B =10^-7  (2 x 3.14 x 100 x 0.4/ 8 x 10^-2)