A current loop in a magnetic field

Options

A. Experiencs a torque whether the field is unifrom or nonuuniform in all orientations
B. Can be in equilibrium in one orientation
C. Can be in equilibrium in two orientrations, both the equilibrium states are unsatable
D. Can be in equilibriuim in tow orientations, one stable while the other in unstable.

Answer

D

Explanation

Parallel `vec(M)` stable
Anti-parallel `vec(M)` unstable
`lambda = (h)/(p) = ((6.6xx10^(-34))/(0.83xx10^(-2)xx2xx1.6xx10^(-19)xx0.25))`
`= 9.94xx10^(-13) m = 0.01 Å`