Paragraph: A point charge Q is moving in a circular orbit of radius R in the x-y plane with an angular velocity . This can be considered as equivalent to a loop carrying a steady current Q 2 . A uniform magnetic field along the positive z -axis is now switched on, which increases at a constant rate from 0 to B in one second. Assume that the radius of the orbit remains constant. The application of the magnetic field i

Step-by-step solution

Magnetic dipole moment M = γ J Δ M = γ Δ J ...(1) Δ J Δ t = - Q dB dt · R 2 R Δ J = - QB 2 R 2 So Δ M = - γ QBR 2 2 Alternate M L = Q 2 m M = Q ω 2 π π R 2 = Q ω R 2 2 induced electric field is opposite to the ω  so the charge is retarded. ω ′ = ω - α t ω ′ = ω - QB 2 1 a t = QE/m , α = QE mR = Q R × BR 2 m = QB 2 m M f = Q ω ′ R 2 2 = Q ω - QB 2 m R 2 2 ∆ M = M f - M