According to coulombs law of electrostatics there is a force between two charged particles q1 & q2 separated by a distance r such that F ∝ q1, F ∝ q2 & F ∝ ; combining all three we get F ∝ or F = , where k is a constant which depends on the medium and is given by 1/4 πε0ε r where ε0 is absolute permittivity & ε r is relative permittivity.But in case of protons of a nuclius there exists another force called nucleur force; which is much higher in magnitude in comparison to electrostatic force and is given by F = .

(i) What are the dimensions of C –