---
title: "System 1 consists of a uniform rod of mass \\(M\\) and length \\(L\\) pivoted at one end. System 2 consists of a massless rod of length \\(L\\) with a point mass of mass \\(M\\) attached to the end opposite the pivot. Both systems are held horizontally and released from rest at time \\(t = 0\\). What is the ratio \\(̑_1 / ̑_2\\) of the magnitude of the initial angular acceleration of System 1 to the magnitude of the initial angular acceleration of System 2?"
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/109826/"
date_modified: "2026-03-26T05:52:43+00:00"
---

# System 1 consists of a uniform rod of mass \(M\) and length \(L\) pivoted at one end. System 2 consists of a massless rod of length \(L\) with a point mass of mass \(M\) attached to the end opposite the pivot. Both systems are held horizontally and released from rest at time \(t = 0\). What is the ratio \(̑_1 / ̑_2\) of the magnitude of the initial angular acceleration of System 1 to the magnitude of the initial angular acceleration of System 2?

System 1 consists of a uniform rod of mass \(M\) and length \(L\) pivoted at one end. System 2 consists of a massless rod of length \(L\) with a point mass of mass \(M\) attached to the end opposite the pivot. Both systems are held horizontally and released from rest at time \(t = 0\). What is the ratio \(̑_1 / ̑_2\) of the magnitude of the initial angular acceleration of System 1 to the magnitude of the initial angular acceleration of System 2?

![Two diagrams side-by-side labeled System 1 and System 2. System 1 shows a thick rectangular rod of length L pivoted at a hinge on the left. System 2 shows a thin line of length L with a large circular point mass at the right end, pivoted at a hinge on the left. Both are horizontal.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-1-1774504363-uDFQG2.jpg)

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

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/109826/*