---
title: "An isolated, uncharged conducting sphere B of radius R is brought into contact with an identical conducting sphere A that initially carries a net charge Q_0. The two spheres reach electrostatic equilibrium and are then separated. What is the ratio U_f / U_i of the total electrostatic potential energy stored in the two-sphere system after separation to the total electrostatic potential energy stored before contact?"
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url: "https://nerd-notes.com/ubq/118206/"
date_modified: "2026-08-04T08:08:10+00:00"
---

# An isolated, uncharged conducting sphere B of radius R is brought into contact with an identical conducting sphere A that initially carries a net charge Q_0. The two spheres reach electrostatic equilibrium and are then separated. What is the ratio U_f / U_i of the total electrostatic potential energy stored in the two-sphere system after separation to the total electrostatic potential energy stored before contact?

An isolated, uncharged conducting sphere B of radius R is brought into contact with an identical conducting sphere A that initially carries a net charge Q_0. The two spheres reach electrostatic equilibrium and are then separated. What is the ratio U_f / U_i of the total electrostatic potential energy stored in the two-sphere system after separation to the total electrostatic potential energy stored before contact?

- **A.** \(\dfrac{1}{2}\)
- **B.** \(\dfrac{3}{4}\)
- **C.** \(1\)
- **D.** \(2\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/118206/*