When the charge on an isolated capacitor is increased by 20 % , the electrostatic energy stored in it increases by 44 J . The original energy stored in the capacitor is

Step-by-step solution

Energy stored in a capacitor is U = Q^2 2C . Let the initial charge be Q₀ and initial energy be U₀ . When the charge is increased by 20 % , the new charge is Q' = Q₀ + 0.2Q₀ = 1.2Q₀ . The new energy is U' = (1.2Q₀)^2 2C = 1.44 ( Q₀^2 2C ) = 1.44 U₀ . The increase in energy is U = U' - U₀ = 1.44 U₀ - U₀ = 0.44 U₀ . Given that U = 44 J , we have: 0.44 U₀ = 44 U₀ = 100 J . Answer: 100 J