# Electric potential problem

1. Jan 11, 2016

### WeiLoong

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

2. Relevant equations
Electric potential
3. The attempt at a solution
Is electric potential a vector quantity?
So that mean both charges product electric potential and result in zero at P?
How should i start for question 17a?

2. Jan 11, 2016

### cnh1995

No. It is scalar.

3. Jan 11, 2016

### QuantumQuest

Electric potential is a scalar. Now, what does it mean that potential at P is zero? You have two isolated point charges, that each one produces an electric field around it. So, how can the potential at P be zero? Answering that, you can immediately see that using this fact and a simple formula, you can calculate point charge at B.

4. Jan 11, 2016

### WeiLoong

That mean kq/r+kq/r=0 something like that?

5. Jan 11, 2016

### QuantumQuest

What would be the potential at point P, if you didn't have point charge at B? But you have this point charge at B and potential at P is zero. So, you have a zero from two scalars (V). What does this imply for the second potential (i.e. regarding B)?

Last edited: Jan 11, 2016