A conducting circular loop is placed in a uniform magnetic field, B =.025 T with its plane perpendicular to the loop. The radius of the loop is made…

A conducting circular loop is placed in a uniform magnetic field, $\displaystyle \mathrm{B}=.025 \mathrm{~T}$ with its plane perpendicular to the loop. The radius of the loop is made to shrink at a constant rate of $\displaystyle 1 \mathrm{~mm} \mathrm{~s}^{-1}$. The induced e.m.f. when the radius is $\displaystyle 2$ cm, is :