Question:
A capacitor having a capacitance of $100 \mu \mathrm{F}$ is charged to a potential difference of $24 \mathrm{~V}$. The charging battery is disconnected and the capacitor is connected to another battery of emf $12 \mathrm{~V}$ with the positive plate of the capacitor joined with the positive terminal of the battery,
(a) Find the charges on the capacitor before and after the reconnection.
(b) Find the charge flown through the $12 \mathrm{~V}$ batteries,
(c) Is work done by the battery or is it done on the battery? Find its magnitude,
(d) Find the decrease in electrostatic field energy, (e) Find the heat developed during the flow of charge after reconnection.
Solution: