Hi, I have this problem in my Physics Book: The electric field everywhere on the surface of a hollow sphere of radius 0.75m is found to be 890 N/C and points radially toward the center of the sphere, (a) What is the net charge within the sphere's surface? (b) What can you tell about the nature of the charge and its distribution inside the sphere? I have answered the first part, it is 5.56x10^-8 C but for the second part, I can't follow the answer (I have it). It says it is negative and uniformly distributed. But I know that: 1- Gauss' law says nothing about charge distribution on a surface. My be due to symmetry, but again, Gauss' law says nothing about charge distribuion. 2- There can be no charges on the inner surface, this will lead to an electric field at the center. The electric field lines will be directed to the center. What is wrong in my understanding?