# Homework Help: Conceptual question help-Electric fields, potentials, etc.

1. Feb 4, 2014

### Hayliee30

Conceptual question help--Electric fields, potentials, etc.

1. The problem statement, all variables and given/known data

1) Assume that the electric field E is equal to zero at a given point. Does it mean the electric potential V must also be equal to zero at this point? If not, provide an example to prove your answer. if you think the answer is "yes," then justify it.

I'm assuming the potential would also have to be zero, right? According to the equation V = E*D, if E is zero...then V would also have to be zero, right? Does the equation apply to all situations...or does it only hold when certain "conditions" are met?

2) 2 small. uniformly charged spheres A & B are at a fixed location. The charge on sphere B is twice the charge on sphere A. Both are positive. What are the directions and relative values of the electostatic forces acting on both spheres?

I know the directions would be in opposite directions of each other. However, the relative value would be..the electrostatic force acting on A would be twice of that when compared to B..since B has twice the charge, right? I'm not really sure on the relative value. If anyone could explain this to me..I would greatly appreciate it.

2. Feb 4, 2014

### BvU

1) You're guessing. Where did you find V = E*D mentioned without there being some "conditions" ?

2) I take it the context is that only electrostatic forces have to be considered. Newton 3 is still valid! Write down each of these forces and draw your conclusions.