Question

A particle of charge $q$ and mass $m$ is clamped rigidly at the circumference of a ring with mass $m$ and radius $R$. Initially ring is in vertical plane resting on a sufficiently rough horizontal surface with charge $q$ at the same horizontal level as that of the centre of the ring. There exists uniform horizontal electric fields as shown.

At $t=0$ the system is let free. (Given that $qE=mg, \pi = \frac{22}{7}$)

Sufficiently rough to avoid slipping The magnitude of the friction force at $t=0$ is

• A. 0

Answer 1

Answer: (A)

0

Answer 2

The magnitude of the friction force at $t=0$ is 0.