Two concentric circular coils with radii 1 cm and 1000 cm, and number of turns 10 and 200 respectively are placed coaxially with centers coinciding.…

Two concentric circular coils with radii $\displaystyle 1$ cm and $\displaystyle 1000$ cm , and number of turns $\displaystyle 10$ and $\displaystyle 200$ respectively are placed coaxially with centers coinciding. The mutual inductance of this arrangement will be $\displaystyle \_\_\_\_$ $\displaystyle \times 10^{-8} \mathrm{H}$. (Take, $\displaystyle \pi^2=10$ )