Question

If distance between plates of a capacitor is decreased by 1% and area of the plates in increased by 2%, what is
the percentage change in the energy it stores if voltage remains same?​

Answer 1

Explanation:

In general capacitance of parallel plate capacitor is given by: 

C=dkϵ0A

where C is capacitance, k is relative permittivity of dielectric material, ϵ0 is permittivity of free space constant, A is area of plates and d is distance between them. 

So as the distance between the plates is increased, its capacity decreases.