Question

A positive point charge q = +2.50 nC is located at x = 1.20 m and a
negative charge of -2q = -5.00 nC is located at the origin.
(a) Find a symbolic expression for the potential on the x – axis at an arbitrary point P between the two
charges.
(b) Find the electric potential at x = 0.600 m.
(c) Find the point along the x –axis between the two charges where the electric potential is zero.

Answer 1

here we have to apply the superposition principle, namely the requested potential, is given by the algebraic sum of the single potentials:

\[\huge V\left( P \right) = K\frac{{ - 2q}}{x} + K\frac{q}{{d - x}}\]
where, as usual, \(K=9 \cdot 10^9\)