Question

$A$ and $B$ are two metallic rings placed at opposite sides of an infinitely long straight conducting wire as shown in the figure. If current in the wire is slowly decreased, then the direction of the induced current will be :

• A. clockwise in $A$ and anticlockwise in $B$.
• B. anticlockwise in $A$ and clockwise in $B$.
• C. clockwise in both $A$ and $B$.
• D. anticlockwise in both $A$ and $B$.

Answer 1

Answer: (B)

anticlockwise in $A$ and clockwise in $B$.

Using the right hand thumb rule, it can be seen that the flux of electric field goes inside the plane of paper in ring B and outside the plane of paper in ring A.
As the current in the wire decreases, the induced current will try to oppose the change in flux.
Therefore, the direction of induced current in A is anticlockwise and that in B is clockwise