In the previous question, let the ring have non-uniformly distributed charge, and let it be spinning about its axis. Let `F` be the net force on the ring and `tau` be the torque on the ring due to the straight conductor

Options

A. `F != 0, tau != 0`
B. `F = 0, tau != 0`
C. `F != 0, tau = 0`
D. `F = 0, tau = 0`

Answer

D

Explanation

Let charge on ring is `q, I = (q)/(T) = (q)/(2pi//omega) = (q omega)/(2pi)`
Due to long wire, magnetic field will be uniform.
force on ring `= 0`
The directed of magnetic moment and magnetic field will be `theta = 0^(@)` or `180^(@)`
`tau = 0`