Physics - Magnetism Question with Solution | TestHub

Perpendicular distance of centroid from any of the sides will be, $d\tan 60°=2\sqrt{3}$

$\Rightarrow d=2 \mathrm{cm}$

Each side will subtend an angle of $120°$ at the centre. Also magnetic field due to all sides will be out of plane of paper, hence total magnetic field can be written as

$B=3\times \frac{{\mu }_{0}i}{4\mathrm{\pi d}}\left[\sin 60°+\sin 60°\right]$

$=3\times \frac{{10}^{-7}\times 2}{2\times {10}^{-2}}\times \sqrt{3}$

$=3\sqrt{3}\times {10}^{-5} \mathrm{T}$