An ideal parallel-plate capacitor consists of a set of two parallel plates of area a separated by a very small distance d. when this capacitor is connected to a battery that maintains a constant potential difference between the plates, the energy stored in the capacitor is u0. if the separation between the plates is doubled, how much energy is stored in the capacitor? an ideal parallel-plate capacitor consists of a set of two parallel plates of area a separated by a very small distance d. when this capacitor is connected to a battery that maintains a constant potential difference between the plates, the energy stored in the capacitor is u0. if the separation between the plates is doubled, how much energy is stored in the capacitor? u0/2 u0 u0/4 4u0 2u0