Question

Determine the electric potential at the midpoint of the line joining two charges 2 × 10^-6 C and -1 × 10^-6 C placed in vacuum 10cm apart.

Answer 1

Data: q₁ = 2 × 10^-6C, q₂ = -1 × 10^-6 C,

r = \(\cfrac{10\,cm}2\) = 5cm = 0.05m,

1/4πε₀ = 9 × 10⁹ N∙m²/C²

The electric potential at a distance r from a charge q is

V = \(\cfrac{q}{4πε_0r}\)

Since potential is a scalar quantity, the total electric potential at the midpoint is