# Net Electric Potential

1. Oct 19, 2004

### rishid

Need a little help with a homework problem, I don't seem to understand the theory behind this.

Figure 25-23 shows four pairs of charged particles. Let V = 0 at infinity.

http://www.webassign.net/hrw/25_23.gif
Figure 25-23.

(a) For which pairs is there another point of zero net electric potential on the axis M between the particles?
ChkBox 4
ChkBox 2
ChkBox none
ChkBox 1
ChkBox 3

(b) For which pairs is there another point of zero net electric potential on the axis M to their right?
ChkBox 2
ChkBox 1
ChkBox 4
ChkBox none
ChkBox 3

If you can just give me some hints on where to start or what to look for, would appreiciate it.

RishiD

2. Oct 20, 2004

### spacetime

The electric potential is given by

$$V = \frac{kQ}{r}$$

So, you need to add the potentials of both the charges in all the situations at the place where the potential is desired. ( put proper sign of the charge ).

Without doing the calculations, you can see where the potential can come out be zero. ( if you take care of the negative and positive terms )

spacetime
www.geocities.com/physics_all/index.html