---
title: "Two isolated systems of charged particles are held at a fixed separation distance \\(d\\) in vacuum, with electric potential energy defined to be zero at infinite separation. System 1 consists of two protons, and System 2 consists of one proton and one electron. What are the signs of the total electric potential energy of System 1 and System 2?"
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url: "https://nerd-notes.com/ubq/121040/"
date_modified: "2026-08-23T04:57:31+00:00"
---

# Two isolated systems of charged particles are held at a fixed separation distance \(d\) in vacuum, with electric potential energy defined to be zero at infinite separation. System 1 consists of two protons, and System 2 consists of one proton and one electron. What are the signs of the total electric potential energy of System 1 and System 2?

Two isolated systems of charged particles are held at a fixed separation distance \(d\) in vacuum, with electric potential energy defined to be zero at infinite separation. System 1 consists of two protons, and System 2 consists of one proton and one electron. What are the signs of the total electric potential energy of System 1 and System 2?

- **A.** System 1: Positive ; System 2: Negative
- **B.** System 1: Positive ; System 2: Positive
- **C.** System 1: Negative ; System 2: Negative
- **D.** System 1: Negative ; System 2: Positive

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/121040/*