An particle is moving along a circle of radius R with a constant angular velocity . Point A lies in the same plane at a distance 2R from the centre. The point A records magnetic field produced by particle. If the minimum time interval between two successive times at which A records zero magnetic field is ‘t’, the angular speed , in terms of t is:
‘A’ records zero magnetic field when particle is moving on a line which passes through A, which happen when tangent to path passes through A. Angle covered between two such point B and as shown in figure.
Time taken to go from B to C is given as