Physics - Capacitor Question with Solution | TestHub

A parallel plate capacitor of capacitance $\mathrm{C}$ is connected to a battery and is charged to a potential difference $\mathrm{V}$. Another capacitor of capacitance $2\mathrm{C}$ is similarly charge to a potential difference $2\mathrm{V}$. The charging battery is now disconnected and the capacitors are connected in parallel to each other in such a way that the positive terminal of one is connected to the negative terminal of the other. The final energy of the configuration is