Each plate of a parallel plate capacitor has a charge $q$ on it. The capacitor is now connected to a battery. Now, which of the following options are correct?
a) The facing surfaces of the capacitor have equal and opposite charges.
b) The two plates of the capacitor have equal and opposite charges.
c) The battery supplies equal and opposite charges to the two plates.
d) The outer surfaces of the plates have equal charges.
Before the battery is connected,
Applying Gauss Law, the inner surfaces of both the plates will have no charge on them, the outer surfaces will have charge $q$.
After the battery is connected,
The potential difference across the capacitor will gradually become equal to that of the battery .The inner surfaces will have equal and opposite charges according to $Q=CV$ where $V$ is the potential difference across the battery.
But, what will be the charges on the outer surfaces of the two plates ?
I am not clear about the role of battery in affecting the charges on the surfaces of the plates.
Option a) Looks right - Not sure about the other options.
Kindly explain what happens to the plates of the capacitor after the battery is connected ?
Does a battery always produce equal amount of negative and positive charges or it may produce additional charges ?