Two Concentric circular coils x and y of radii $16\;cm$ and $10\;cm$ respectively lie in the same vertical plane containing the north to south direction . coil x has 20 turns and carries a current of $16\;A$ coil y has 25 turns and carries a current of 18 A. The sense of the current in x is anticlock and clock wise in y, for an observe looks at the coils facing west. Find the magnitude and direction of the net magnetic force due to the coils at their center.

Question

$\begin{array}{1 1} 15.7 \times 10^{-3}T \;towards\;east \\ 15.7 \times 10^{-3}T \;towards\;west \\ 15.7 \times 10^{-4}T \;towards\;east \\ 15.7 \times 10^{-4}T \;towards\;west \end{array} $