A long, circular pipe, with an outside radius R, carries a (uniformly distributed)
Channel: Doubtnut
Date: 2020-07-26

A long, circular pipe, with an outside radius R, carries a (uniformly distributed) current `i_0` (into the paper as shown in Fig.) A wire runs parallel to the pipe at a distance 3R from centre to centre. Calculate the magnitude and direction of the current in the wire that would cause the resultant magnetic field at point P to have the same magnitude, but the opposite direction, as the resultant field at the centre of the pipe.