Question

Figure illustrates plane figures made of thin conductors which are located in a uniform magnetic fields directed away from a reader beyond the plane of the drawing. The magnetic induction starts diminishing. Find how the currents induced in these loops are directed.

Answer 1

According to Lenz, the sense of induced e.m.f. is such that it opposes the cause of change of flux. In our problem, magnetic field is directed away from the reader and is diminishing.
So, in figure (a), in the round conductor, it is clockwise and there is no current in the connector
In figure (b) in the outside conductor, clockwise.
In figure (c) in both the conductor, clockwise; and there is no current in the connector to obey the charge conservation.
In figure (d) in the left side of the figure, clockwise.