A coil of inductance $\mathrm{L}=50\mathrm{\mu H}$ and resistance=$0.5\mathrm{\Omega }$  is connected to a battery of emf=5V.A resistance of  $10\mathrm{\Omega }$ is connected parallel to the coil. Now at some instant the connection of the battery is switched off. Then, the amount of heat generated in the coil after switching off the battery is  $\left(0.02\right)\text{x\hspace{0.17em}}\mathrm{in}\mathrm{mJ}$. Find value of $x$ (to the nearest integer)