Two iclentical short bar magnets, each having magnetic moment \(\mathrm{M}\) are
placed a distance of \(2 \mathrm{~d}\) apart with axes perpendicular to each
other in a horizontal plane. The magnetic induction at a point midway between
them is.
(a) $\sqrt{2}\left(\mu_{0} / 4 \pi\right)\left(\mathrm{M} /
\mathrm{d}^{3}\right)$
(b) $\sqrt{3}\left(\mu_{0} / 4 \pi\right)\left(\mathrm{M} /
\mathrm{d}^{3}\right)$
(c) $\sqrt{4}\left(\mu_{0} / 4 \pi\right)\left(\mathrm{M} /
\mathrm{d}^{3}\right)$
(d) $\sqrt{5}\left(\mu_{0} / 4 \pi\right)\left(\mathrm{M} /
\mathrm{d}^{3}\right)$