---
title: "A uniform thin rod of mass \\(M\\) and length \\(L\\) is attached to a frictionless horizontal axle at one end. A small block of mass \\(2M\\) is fixed to the rod at a distance of \\(\\dfrac{3}{4}L\\) from the axle. The system is held in a horizontal position and released from rest. At the instant of release, what is the magnitude of the angular acceleration of the rod-block system?"
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url: "https://nerd-notes.com/ubq/112823/"
date_modified: "2026-05-01T18:12:59+00:00"
---

# A uniform thin rod of mass \(M\) and length \(L\) is attached to a frictionless horizontal axle at one end. A small block of mass \(2M\) is fixed to the rod at a distance of \(\dfrac{3}{4}L\) from the axle. The system is held in a horizontal position and released from rest. At the instant of release, what is the magnitude of the angular acceleration of the rod-block system?

A uniform thin rod of mass \(M\) and length \(L\) is attached to a frictionless horizontal axle at one end. A small block of mass \(2M\) is fixed to the rod at a distance of \(\dfrac{3}{4}L\) from the axle. The system is held in a horizontal position and released from rest. At the instant of release, what is the magnitude of the angular acceleration of the rod-block system?

![A horizontal rod of length L is shown. The left end of the rod is attached to a circular pivot on a wall. A small square block is attached to the rod at a point three-quarters of the way from the pivot to the right end. A dashed vertical line indicates the gravitational field vector g pointing downward.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-1-1777659179-LZ2G00.jpg)

- **A.** \(\dfrac{48g}{35L}\)
- **B.** \(\dfrac{16g}{11L}\)
- **C.** \(\dfrac{3g}{2L}\)
- **D.** \(\dfrac{12g}{7L}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/112823/*