A circular wire loop of radius a has N turns and carries a current L A second loop with N' turns of radius a' carries current I' and is located on the axis of the first loop, a distance x from the center of the first loop. The second loop is tipped so that its axis is at an angle θ from the axis of the first loop. The distance x is large compared to both a and a'.
(a) Find the magnitude of the torque exerted on the second loop by the first loop.
(b) Find the potential energy for the second loop due to this interaction.
(c) What simplifications result from having x much larger than a from having x much larger than a'?