Question

A charged particle is moving on a circular path of radius R and there is a point P at distance 2R from centre in same plane of circular path. Then find minimum time interval between two successive times at which magnetic field at point P will be zero.

Answer 1

periodic time, $T=2\pi/\omega$

time, t=$T/3=1/3\times 2\pi/\omega=2\pi/3\omega$