A single current-carrying circular loop of radius R is placed next to a long,straight wire,as shown in the figure.The current I in the wire flows to the right.In which direction must current flow in the loop to produce a net magnetic field of zero at its center?

Question

Quizplus · Accepted Answer

According to the right-hand rule, the magnetic field produced by the current in the long, straight wire will be clockwise around the wire. To cancel out this magnetic field at the center of the circular loop, the magnetic field produced by the current in the loop must be in the opposite direction, i.e., counterclockwise. Therefore, to produce a net magnetic field of zero at the center, the current in the loop must flow clockwise.

A Single Current-Carrying Circular Loop of Radius R Is Placed