An electrostatic force between two point charges increases when they are:

Coulomb's law in Electrostatics:

It state’s that force of interaction between two stationary point charges is directly proportional to the product of the charges, and inversely proportional to the square of the distance between them and acts along the straight line joining the two charges.

F ∝ q1 × q2

Where K = constant depends on dielectric constant is given by:

where ϵ  is the dielectric constant .

Observation:

• The electrostatic force will increase when 'r' is small, i.e. when the charges are less apart.
• The electrostatic force will increase when the dielectric constant 'ϵ' is small.
• The force also depends on the magnitude of the charges.