The figure shows planar loops of different shapes moving out of or into a region of a magnetic field which is directed normal to the plane of the loop away from the reader. Determine the direction of induced current in each loop using Lenz's law.

(N/A) $(i)$ The magnetic flux through the rectangular loop $abcd$ increases due to the motion of the loop into the region of the magnetic field. The induced current must flow along the path $bcdab$ so that it opposes the increasing flux.
$(ii)$ Due to the outward motion,the magnetic flux through the triangular loop $abc$ decreases,due to which the induced current flows along $bacb$ to oppose the change in flux.
$(iii)$ As the magnetic flux decreases due to the motion of the irregular-shaped loop $abcd$ out of the region of the magnetic field,the induced current flows along $cdabc$ to oppose the change in flux.
Note that there is no induced current as long as the loops are completely inside or outside the region of the magnetic field.