Electric field halfway between dipole isn't 0?

[MCATPhys]

I was just wondering... say you have a dipole, and you wanted to find the net electric field right in the middle.

The electric field from the electron will be:
E = k(-1.60*10^-19)/r^2


The electric field from the proton will be the same magnitude, but opposite direction. Therefore, the net electric field should be zero right?

 

[CanIExplore]

Say the dipole is located at the origin and oriented along they y axis. If the electron is at x=-a and the proton at x=a then they both contribute equally to the magnitude of E at the origin as you said, but think about the direction in which the E vector at the origin points due to each particle again. For a positive charge E points away and for a negative charge E points towards right?

 

[MCATPhys]

ohhh - so since they are both in the same direction... they add to a non-zero number...?

 

[CanIExplore]

Correct. They both point in the same direction, that is, in the direction from the proton to electron. So the field there is nonzero.

 

[Antiphon]

It's very large in between the charges.
If the charges were the same polarity there would be zero field at a point but this isn't a dipole.