---
title: "An air-filled parallel-plate capacitor with plate separation \\(d\\) is connected to a battery that maintains a constant potential difference \\(V_0\\). While the capacitor remains connected to the battery, the distance between the plates is increased to \\(2d\\). What is the ratio \\(U/U_0\\) of the final stored electric potential energy \\(U\\) to the initial stored energy \\(U_0\\)?"
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/118183/"
date_modified: "2026-08-04T08:07:56+00:00"
---

# An air-filled parallel-plate capacitor with plate separation \(d\) is connected to a battery that maintains a constant potential difference \(V_0\). While the capacitor remains connected to the battery, the distance between the plates is increased to \(2d\). What is the ratio \(U/U_0\) of the final stored electric potential energy \(U\) to the initial stored energy \(U_0\)?

An air-filled parallel-plate capacitor with plate separation \(d\) is connected to a battery that maintains a constant potential difference \(V_0\). While the capacitor remains connected to the battery, the distance between the plates is increased to \(2d\). What is the ratio \(U/U_0\) of the final stored electric potential energy \(U\) to the initial stored energy \(U_0\)?

- **A.** \(\dfrac{1}{4}\)
- **B.** \(\dfrac{1}{2}\)
- **C.** \(1\)
- **D.** \(2\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/118183/*