The two charges in the figure below are separated by d = 4.00 cm. (Let q1 = -16 nC and q2 = 26.5 nC.)

(a) Find the electric potential at point A.

(b) Find the electric potential at point B, which is halfway between the charges.

Question

The two charges in the figure below are separated by d = 4.00 cm. (Let q1 = -16 nC and q2 = 26.5 nC.)

(a) Find the electric potential at point A.
  

(b) Find the electric potential at point B, which is halfway between the charges.

anonymous · Answer

$$U(r) = \frac{1}{4\pi \epsilon_0}*\frac{q}{r}$$
is the formula for electric potential due to a point charge at distance r with a charge of q. Epsilon in the equation is vacuum permittivity. U(r) is a linear function so you just need to sum up the potentials created by both of the charges.