In which region is it possible for electric potential = 0?

1. Feb 2, 2015

pinkie9211

Two charges that are shown:
I (4uC) II (-2uC) III
In which regions all the line connecting the charges is it possible for the electric potential to be zero?

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

They are 0.01m apart

2. Relevant equations

3. The attempt at a solution
I understand that the 4uC charge and the -2uC charge are going to attract...but I have no idea where the potential could be equal to zero.

2. Feb 2, 2015

Simon Bridge

Hint:
What is the equation for the electric potential of a point charge?
What si the rule for combining electric potentials?

3. Feb 2, 2015

pinkie9211

V= kQ/r

and I'm not sure...

4. Feb 2, 2015

Simon Bridge

Indeed $V(\vec r)=kQ/r$ for a point charge $Q$ at the origin.
If you have two or more charges, then the electric potentials add up.