Two circular current loops are centered on the z axis at z = ±h. Each loop has radius a an...

Two circular current loops are centered on the z axis at z = ±h. Each loop has radius a and carries current I in the aϕ direction. (a) Find H on the z axis over the range −h < z<h. Take I = 1 A and plot |H| as a function of z/a if

Figure 7.21 See Problem 7.5.

(b) h = a/4; (c) h = a/2; (d) h = a. Which choice for h gives the most uniform field? These are called Helmholtz coils (of a single turn each in this case), and are used in providing uniform fields.