Consider a magnetic dipole μ in magnetic field B. Show that the energy difference of the states between the maximal and minimal values is 2μB. (10%) A magnetic dipole in an external magnetic field has a magnetic potential energy that depends on the dipole's orientation in the field. We find that the potential energy U at any angle θ is U(θ) = - μBcosθ An magnetic dipole has its lowest energy(= -μBcos0 = -μB) when its dipole moment is lined up with the magnetic field B. It has its highest energy(= -μBcos180°= +μB) when vector μ is directed opposite the field. So the energy difference of the states between the maximal and minimal values is U(180°) - U(0°) = +μB - (-μB) = 2μB --

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