I need help with something.I have problem to understand how the capacitance of a capacitor can be increased if we move the plates of the capacitor more close.

Here's my reasoning:

The capacitor is just a extended terminal of a battery,so the battery voltage must equal the capacitor voltage.Because the area of the plates of the capacitor is larger than,that of the battery, the plates of the capacitor can accumulate charge until the battery and the capacitor have the same voltage.This is logical for me and I can make a mental picture from it.]/QUOTE]

If your mental picture says that, I regret to inform you that it's wrong. Very wrong.

Whenever you connect open-circuited conductors to battery terminals, the conductors will assume the same potential as the battery. Whether those conductors are called capacitors or not doesn't matter at all. The battery will move charge from one conductor to another until the potentials equal those of the battery. All that happens in the blink of an eye, as they say.

I cannot understand how the capacitance can be increase, and voltage not if we move the plates more close.I understand that if we move the plates more close,the positive plate will affect the negative and more charge will accumulate on the negative plate,but if more charge accumulate on the same square are of the plates,that mean that we will have bigger voltage on the capacitor.

Capacitance is a measure of charge displaced per volt. The closer the plates, the greater the electrostatic forces between them, for a given voltage. That means more charge displaced, and thus more capacitance.

[QUOTE[For example if we have 1 farad capacitor and the voltage is one volt,we will have one coulomb of charge on the plates.But if we bring the plates more close, then the voltage would be the same but will will have more charge on the same area plates.If we have more charge on a plate with a same area then, the repulsive forces between the electrons should make the voltage bigger.

Thank to anyone who can help me with this.I'm struggling to understand this.