A uniform magnetic field B of 0 .3 T is along the positive Z -direction. A rectangular loop ( a b c d ) of sides 10 cm × 5 cm carries a current I of 12 A . Out of the following different orientations which one corresponds to stable equilibrium?

Step-by-step solution

U = - M → · B → = - M B cos θ For stable equilibrium potential energy should be minimum and τ = 0 U m i n = - M B        when   θ = 0 ° ⇒ cos ⁡ θ   = 1 ⇒ M →  and   B → are on same direction.