A capacitor is attached across a battery and charged. Then the battery is removed leaving the capacitor charged. The positive lead of the capacitor is then connected to one lead of a previously uncharged identical capacitor, and then the other lead of the charged capacitor is connected to the other lead of the second capacitor. How does the energy E₀ stored in the originally charged capacitor compare to the energy E_f stored in the connected capacitors?

Question

Quizplus · Accepted Answer

When the charged capacitor is connected to the uncharged capacitor, the charge is redistributed equally between the two capacitors. The total energy is conserved, but the energy is now shared between two capacitors, resulting in each having half the initial energy, making the final energy E_f half of E₀. Thus, E₀ = 2E_f.

A Capacitor Is Attached Across a Battery and Charged