---
title: "A uniform thin rod of mass \\(M\\) and length \\(L\\) is initially at rest in deep space in an inertial reference frame. A small clay projectile of mass \\(m\\) travels with constant speed \\(v_0\\) perpendicular to the rod and collides with and sticks to one end of the rod. Which of the following correctly describes the conservation of the total angular momentum and the change in total mechanical energy of the rod-projectile system during the collision?"
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url: "https://nerd-notes.com/ubq/120934/"
date_modified: "2026-08-23T04:44:24+00:00"
---

# A uniform thin rod of mass \(M\) and length \(L\) is initially at rest in deep space in an inertial reference frame. A small clay projectile of mass \(m\) travels with constant speed \(v_0\) perpendicular to the rod and collides with and sticks to one end of the rod. Which of the following correctly describes the conservation of the total angular momentum and the change in total mechanical energy of the rod-projectile system during the collision?

A uniform thin rod of mass \(M\) and length \(L\) is initially at rest in deep space in an inertial reference frame. A small clay projectile of mass \(m\) travels with constant speed \(v_0\) perpendicular to the rod and collides with and sticks to one end of the rod. Which of the following correctly describes the conservation of the total angular momentum and the change in total mechanical energy of the rod-projectile system during the collision?

![A schematic diagram viewed from above on a clean background. A vertical rectangle representing a uniform rod of length \(L\) and mass \(M\) is centered vertically. A small filled black circle representing a projectile of mass \(m\) is positioned to the left of the upper end of the rod. A horizontal straight arrow labeled \(v_0\) points directly from the small circle toward the upper tip of the rod, indicating motion perpendicular to the rod. A double-ended vertical dimension arrow labeled \(L\) runs parallel to the rod on its right side, spanning from the top end to the bottom end. The label \(M\) is placed directly next to the center of the rod. The label \(m\) is placed directly above the small circle. No other labels, lines, text, or axes appear.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-1-1787460264-R9IhCe.jpg)

- **A.** Total Angular Momentum: Conserved about any point fixed in the inertial frame; Total Mechanical Energy: Strictly decreases
- **B.** Total Angular Momentum: Conserved about any point fixed in the inertial frame; Total Mechanical Energy: Conserved
- **C.** Total Angular Momentum: Conserved only about the system's center of mass; Total Mechanical Energy: Strictly decreases
- **D.** Total Angular Momentum: Conserved only about the system's center of mass; Total Mechanical Energy: Conserved

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/120934/*