Consider a circular current-carrying loop of radius R in the x-y plane with centre at origin. Consider the line intergral
(a) Show that ℑ (L) monotonically increases with L.
(b) Use an appropriate Amperian loop to show that ℑ (∞)= μ0I , where I is the current in the wire.
(c) Verify directly the above result.
(d) Suppose we replace the circular coil by a square coil of sides R carrying the same current I. What can you say about ℑ(L ) andℑ(∞) ?