Physics

Problem

Two point charges

+q

and

-q

are placed

10\,\text{cm}

apart on a straight line. Point

P

lies exactly midway between them on the line joining the charges. What is the electric potential at

P

? a)

+\dfrac{1}{4\pi\varepsilon_0}\,\dfrac{2q}{0.05\,\text{m}}

+\dfrac{1}{4\pi\varepsilon_0}\,\dfrac{2q}{0.10\,\text{m}}

c) Zero, because the potentials due to the two charges cancel each other d) Infinite, because the electric field at

P

is zero