A charge of magnitude +2q is fixed at the origin. A second charge, −q, is fixed at a distance d away from the origin on the positive x axis.
a. Find the point(s) where the electric potential is zero?
b. How many points have an electric potential of zero?
c. How many points have an electric field of zero?

Explanation:

(a)   Let us assume that the potential at point x is equal to zero.

Then,

          = 0

          = 0

                 2d - 2x = -x

             -x + 2x = 2d

or,            x = 2d

Therefore, at a point x = 2d the electric potential is equal to zero.

(b)   There will be only one point where an electric potential is zero and that point is x = 2d.

(c)  Let us assume that and are electric fluids because of the charge +2q and -q respectively.

So, there is only one point where the charge can be zero and that point is D.

a.) travels faster in solids because the particles are closer together.

air is a gas water is a liquid