Question

When an air capacitor with a capacitance of 400 (1 = ) is connected to a power supply, the energy stored in the capacitor is 2.05×10−5 . While the capacitor is kept connected to the power supply, a slab of dielectric is inserted that completely fills the space between the plates. This increases the stored energy by 2.28×10−5

Answer 1

And the question is....