Two identical thin bar magnets, each of length L and pole strength m are placed at right angles to each other, with the north pole of one touching the south pole of the other . Find the magnetic moment of the system.

Question

$\begin{array}{1 1} 2mL \\ \sqrt 2 mL \\ \large\frac{2m}{L} \\ \large\frac{\sqrt 2 m}{L} \end{array}$