part a\nfind the energy u0 stored in the capacitor.\nexpress your answer in terms of a, d, v, and ε0…

part a\nfind the energy u0 stored in the capacitor.\nexpress your answer in terms of a, d, v, and ε0. remember to enter ε0 as epsilon_0.\nview available hint(s)\nu0 =\nsubmit\npart b\nthe capacitor is now disconnected from the battery, and the plates of the capacitor are then slowly pulled apart until the separation reaches 3d. find the new energy u1 of the capacitor after this process.
Answer
Explanation:
Step1: Recall capacitance formula
The capacitance of a parallel - plate capacitor is $C_0=\frac{\epsilon_0A}{d}$.
Step2: Recall energy formula for capacitor
The energy stored in a capacitor is $U = \frac{1}{2}CV^{2}$. Substitute $C_0$ into the energy formula: $U_0=\frac{1}{2}C_0V^{2}=\frac{1}{2}\times\frac{\epsilon_0A}{d}\times V^{2}=\frac{\epsilon_0AV^{2}}{2d}$.
Answer:
$U_0=\frac{\epsilon_0AV^{2}}{2d}$