Charge q is uniformly spread on a thin ring of radius R. The ring rotates

Charge q is uniformly spread on a thin ring of radius R. The ring rotates about its axis with a uniform frequency f Hz. The magnitude of magnetic induction at the centre of the ring is

Options

(a) µ₀q f / 2 R
(b) µ₀q / 2 f R
(c) µ₀q / 2π f R
(d) µ₀q f / 2π R

Correct Answer:

µ₀q f / 2 R

Explanation:

When the ring rotates f Hz, the current flowing in the ring is i = q/T = qf
Magnetic field at the centre of the ring is
B = µ₀I / 2 R = µ₀q f / 2 R

admin:

Related Questions

  1. A short linear object of length L lies on the axis of a spherical mirror of focal
  2. A conveyor belt is moving at a constant speed of 2 m/s. A box is gently dropped on it
  3. Charge passing through a conductor of cross-section area A=0.3 m² is given
  4. A copper disc of radius 0.1 m is rotated about its centre, with 10 revolutions
  5. A boy playing on the roof of a 10m high building throws a ball with a speed