A conducting metal circular-wire-loop of radius r is placed perpendicular to a magnetic field which varies with time as B=B_0 e^-t / τ, where B_0 and…

A conducting metal circular-wire-loop of radius $\displaystyle r$ is placed perpendicular to a magnetic field which varies with time as $\displaystyle B=B_0 \mathrm{e}^{-t / \tau}$, where $\displaystyle B_0$ and $\displaystyle \tau$ are constants, at time $\displaystyle t=0$. If the resistance of the loop is $\displaystyle R$ then the heat generated in the loop after a long time $\displaystyle (t \rightarrow \infty)$ is :