Question

An outer metal ring surrounds an inner metal ring, as shown in the figure. The current in the outer ring is counter-clockwise and increasing. What is the direction of the induced current in the inner ring?

Answer 1

Take into account that the current in the wire is clockwise, it generates a magnetic field which points out of the plane.

Due to the current in the wire increases, the strengh of the magentic field increases too.

Accordint to the Lenz's law, the induced current in the inner wire produced a magnetic field which is opposite to the magentic field generated by the outer ring. It means that the induced current is counterclockwise.