Physics - Magnetism Question with Solution | TestHub

Torque,$\mathrm{\tau }=\mathrm{MB} \sin \mathrm{\theta }$

Where$\mathrm{\theta }=90°$

$\therefore \mathrm{\tau }=\mathrm{MB}$

Given,${\mathrm{\tau }}_2=\frac{1}{2\mathrm{ }}{\mathrm{\tau }}_1$

$\therefore \mathrm{MB}\mathrm{ }\sin \mathrm{\theta }=\frac{1}{2}\mathrm{ }\mathrm{MB}$

$\therefore \mathrm{sin \theta }=\frac{1}{2}\mathrm{ }$

$\Rightarrow \mathrm{\theta }=30°$

Angle of rotation$=90°-30°=60°$