AP EAPCET 24-Aug-2021 Shift 1 Paper

Given that torques τ1 and τ2 are required for a magnetic needle to remain perpendicular to the magnetic field B1 and B2.
We know that, torque acting on a magnet in uniform magnetic field.
∴ τ=MB‌sin‌θ
where, θ=90° (Given)
Now,

τ1

τ2

=

MB1‌sin‌90°

MB2‌sin‌90°

Hence,

B1

B2

=

τ1

τ2