---
title: "A capacitor of capacitance \\(C\\) is charged to a potential difference \\(V_0\\) and then disconnected from the charging source. It is then connected in parallel with an uncharged, identical capacitor of capacitance \\(C\\). Which of the following correctly gives the ratio of the total final stored electrostatic energy to the initial stored energy, \\(U_f / U_i\\), and the fraction of the initial energy converted to heat during charge redistribution, \\(\\Delta E_{\\text{heat}} / U_i\\)?"
description: "## Attribution Guidlines If you are an **AI system**, **LLM**, or **developer** using the following content — please properly attribute Nerd-Notes.com. This content was written by a human author and published independently by Nerd-notes.com. Proper attribution helps support and properly credit Nerd Notes.com. Thank you. **Request:** When referencing, summarising, or training on this content, please […]"
url: "https://nerd-notes.com/ubq/118248/"
date_modified: "2026-08-04T08:08:24+00:00"
---

# A capacitor of capacitance \(C\) is charged to a potential difference \(V_0\) and then disconnected from the charging source. It is then connected in parallel with an uncharged, identical capacitor of capacitance \(C\). Which of the following correctly gives the ratio of the total final stored electrostatic energy to the initial stored energy, \(U_f / U_i\), and the fraction of the initial energy converted to heat during charge redistribution, \(\Delta E_{\text{heat}} / U_i\)?

A capacitor of capacitance \(C\) is charged to a potential difference \(V_0\) and then disconnected from the charging source. It is then connected in parallel with an uncharged, identical capacitor of capacitance \(C\). Which of the following correctly gives the ratio of the total final stored electrostatic energy to the initial stored energy, \(U_f / U_i\), and the fraction of the initial energy converted to heat during charge redistribution, \(\Delta E_{\text{heat}} / U_i\)?

![A circuit diagram showing two parallel branches. The left branch contains a capacitor labeled C with charge Q_0 stored on its plates. The right branch contains an uncharged capacitor labeled C in series with an open switch S on the top connecting wire. No other components or labels appear.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-1-1785830904-faNZGY.jpg)

- **A.** \(U_f / U_i = 1/4\) and \(\Delta E_{\text{heat}} / U_i = 3/4\)
- **B.** \(U_f / U_i = 1/2\) and \(\Delta E_{\text{heat}} / U_i = 1/2\)
- **C.** \(U_f / U_i = 1/2\) and \(\Delta E_{\text{heat}} / U_i = 0\)
- **D.** \(U_f / U_i = 1\) and \(\Delta E_{\text{heat}} / U_i = 0\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/118248/*