Suppose we have an un-charged parallel plate capacitor separated by some distance (say d). As the capacitor is not charged, the plates are in neutral position. Means, it has equal no. of electrons and protons. So, Potential difference across the plates is 0 because energy possessed by 1 C of charge is same on both plates. Now when we connect the capacitor with a battery, having potential difference ##3V##, then the left plate of the capacitor will acquire positive charge as electron will be attracted towards the positive terminal of the battery and hence pushed by negative terminal of the battery towards the right plate of the capacitor. Meanwhile as electrons passes through the battery, 1 C of charge will acquire 3 J of energy. When whole electrons are settled on the right plate of the capacitor, we will have a potential difference of 3V at the terminals of the capacitor because each coulomb of charge has gained 3 J of energy. Now my doubt is 1) Does my above understanding is right or it has some misconceptions 2) As we connect a capacitor to the battery using conducting wire, Conducting wires also has electrons and protons. Do we have to consider them also. In all online Lectures & articles, No body has considered the electrons and protons in connecting wires.