Fig. shows planer loops of different shapes moving out of or into a region of magnetic field which is directed normal to the plane of the loops away from the reader. Determine the direction of induced current in each loop using Lenz's law. Check if you would obtain the same answers by considering magnetic force on the charge inside the moving loops.

Explanation

(i) Due to motion, the magnetic flux linked with the loop abcd increases. According to Lenz's law, this increase in flux is opposed by the induced current. Therefore, the induced current must flow along bcdab.
(ii) Due to motion, magnetic flux linked with abc decreases. Induced current is along bacb.
(iii) The magnetic flux increases in this case
Therefore, induced current is anticlockwise.
(iv) As magnetic flux decreases due to motion, the induced current is along cdabc.
Yes, we would obtain the same answers by considering magnetic force on the charges inside the loop.