where $N$ is the number of turns in the coil, $I$ is the current through the coil, $B$ is the uniform magnetic field, $A$ is the area of the coil and $\theta$ is the angle between the direction of the magnetic field and nomal to the plane of the coil. Here, $N=50, I=2\, \mathrm{A},$

$A=0.12\, \mathrm{m} \times 0.1\, \mathrm{m}=0.012\, \mathrm{m}^{2}$

$B=0.2\, \mathrm{Wb} / \mathrm{m}^{2} \text { and } \theta=90^{\circ}-30^{\circ}=60^{\circ}$

$\therefore \quad \tau =(50)(2\, \mathrm{A})\left(0.012\, \mathrm{m}^{2}\right)\left(0.2\, \mathrm{Wb} / \mathrm{m}^{2}\right) \sin 60^{\circ} $

$=0.20\, \mathrm{N} \mathrm{m}$