Electric Field and Electric Potential

AI Thread Summary
For a uniformly charged sphere of radius R with charge Q, the electric field E and electric potential V are analyzed for distances inside (r < R) and outside (r > R) the sphere. Inside the sphere, the correct answers are E = 0 and V = kQ/R, indicating that the electric field is zero while the potential remains constant. Outside the sphere, the electric field is represented as E = kQ/(r^2) and the potential as V = kQ/r, showing that both quantities decrease with distance. The discussion highlights the relationship between electric field and potential, emphasizing that a zero electric field does not imply zero potential. The final consensus confirms the answers as B for r < R and D for r > R.
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[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!
 
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nm i got it.
 


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?
 
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