A rectangular, a square , a circular and an elliptical loop, all in the `(x-y)` plane, are moving out of a uniform magnetic field with a constant velocity `vec(v)=vhati` . The magnetic field is directed along the negative `z`-axis direction. The induced emf, during the passage of these loops , out of the field region, will not remain constant for :

Options

A. the circular and the elliptical loops.
B. only the elliptical loop
C. any of the four loops
D. the rectangular, circular and elliptical loops.

Answer

A

Explanation

The induced emf will remain constant only in the case of rectangular and square loops. In case of the circular and the elliptical loops, the rate of change of area of the loops during their passage out of the field is not constant, hence induced emf will not remain constant for them.