A solid insulating sphere of radius a carries a net positive charge 3Q, uniformly distributed throughout its volume. Concentric with this sphere is a conducting spherical shell with inner radius b and outer radius c, and having a net charge -Q, as shown in Figure P24.55.
(a) Construct a spherical Gaussian surface of radius r > c and find the net charge enclosed by this surface.
(b) What is the direction of the electric field at r > c?
(c) Find the electric field at r > c.
(d) Find the electric field in the region with radius r where c > r > b.
(e) Construct a spherical Gaussian surface of radius r, where c > r > b, and find the net charge enclosed by this surface.
(f) Construct a spherical Gaussian surface of radius r, where b > r > a, and find the net charge enclosed by this surface.
(g) Find the electric field in the region b > r > a.
(h) Construct a spherical Gaussian surface of radius r , a, and find an expression for the net charge enclosed by this surface, as a function of r. Note that the charge inside this surface is less than 3Q.
(i) Find the electric field in the region r , a.
(j) Determine the charge on the inner surface of the conducting shell.
(k) Determine the charge on the outer surface of the conducting shell.
(l) Make a plot of the magnitude of the electric field versus r

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