Electric field and potential inside and outside a uniformly charged sphere

[Dorney]

[SOLVED] Electric Field and Electric Potential

1. Refer to a sphere of radius R that has a positive charge Q uniformly distributed on its surface.

Which of the fllowing represents the magnitude of the electric field E and the potential V as functions of r, the distance from the center of the sphere, where r < R?

A) E = 0 and V = kQ/R
B) E = 0 and V = kQ/r
C) E = 0 and V = 0
D) E = kQ/(r^2) and V = 0
E) E = kQ/(R^2) and V = 0


Which of the following represents the magnitude of the electirc field E and the potential V as functions of r, the distance from the center of the sphere, where r > R?

A) E = kQ/(R^2) and V = kQ/R
B) E = kQ/R and V = kQ/R
C) E = kQ/R and V = kQ/r
D) E = kQ/(r^2) and V = kQ/r
E) E = kQ/(r^2) and V = kQ/(r^2)


2. E = kq/(r^2) and V = kq/r


3. Thinking it through, I got the answers B and D, respectively.

Thanks in advance!

 

[Dorney]

nm i got it.

 

[resilient]

Is the answer actually B and D?

I'm thinking it might be C and D. Potential is the integration of the electric field dotted with dr. If E is zero, how can there be any potential? Am I wrong?