Two equal point charges exert a force F on each other when they are placed distance 'd' apart in air. When they are placed distance 'D' apart in a medium of dielectric constant K, they exert the same force. The distance D is equal to

Step-by-step solution

The electrostatic force between two point charges in air is given by F = 1 4 ₀ q^2 d^2 When the charges are placed in a medium of dielectric constant K at a distance D , the force is F' = 1 4 ₀ K q^2 D^2 Given that the forces are equal, F = F' : 1 4 ₀ q^2 d^2 = 1 4 ₀ K q^2 D^2 1 d^2 = 1 K D^2 D^2 = d^2 K D = d K Answer: d K