Question

A long wire carrying current I is coplanar with a rectangular loop of wire as shown. What are the directions of the induced current in the loop and the magnetic forces on the left and the right sides as the loop is moved towards the wire?

• A. Induced Current-Counterclockwise, Force on left side-To the left, Force on Right side-To the right
• B. Induced Current-Clockwise, Force on left side-To the left, Force on Right side-To the right
• C. Induced Current-Counterclockwise, Force on left side-To the right, Force on Right side-To the left
• D. Induced Current-Clockwise, Force on left side-To the right, Force on Right side-To the left

Answer 1

The correct option is C Induced Current-Counterclockwise, Force on left side-To the right, Force on Right side-To the left

The field on right side of wire is into the plane and is larger on the left side of loop than the right side.

Hence, emf generated in left loop is larger than that in the right side.

Now, using the induction rule we can easily get that lower end is at higher potential as loop moves leftward..

Hence, the current will be in clockwise direction.

Now, current on left side is downward and field is into the plane hence force is along $\hat{I}\times \hat{B}$ i.e, rightward. And on right side , current is upward and field is downward, so force is leftward.

Hence, option-(C) is correct.