A thin ring of radius 'R' metre has charge 'q' coulomb uniformly spread on it. The ring rotates about its axis with a constant frequency of 'f' revolution/s. The value of magnetic induction at the centre of the ring in Wb/m ^2 is ( ₀ = permeability of free space )

Step-by-step solution

The equivalent current I due to the rotating charge is given by the rate of flow of charge. I = q T = qf The magnetic induction at the centre of a circular current-carrying loop is given by: B = ₀ I 2R Substituting the value of I , we get: B = ₀ qf 2R Answer: ₀ qf 2R