---
title: "A system consists of a disk rotating on a frictionless axle and a piece of clay moving toward it, as shown in the figure above. The outside edge of the disk is moving at a linear speed \\( v \\), and the clay is moving at speed \\( \\frac{v}{2} \\). The clay sticks to the outside edge of the disk. How does the angular momentum of the system after the clay sticks compare to the angular momentum of the system before the clay sticks, and what is an explanation for the comparison?"
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url: "https://nerd-notes.com/ubq/29490/"
date_modified: "2025-03-11T05:17:54+00:00"
---

# A system consists of a disk rotating on a frictionless axle and a piece of clay moving toward it, as shown in the figure above. The outside edge of the disk is moving at a linear speed \( v \), and the clay is moving at speed \( \frac{v}{2} \). The clay sticks to the outside edge of the disk. How does the angular momentum of the system after the clay sticks compare to the angular momentum of the system before the clay sticks, and what is an explanation for the comparison?

A system consists of a disk rotating on a frictionless axle and a piece of clay moving toward it, as shown in the figure above. The outside edge of the disk is moving at a linear speed \( v \), and the clay is moving at speed \( \frac{v}{2} \). The clay sticks to the outside edge of the disk. How does the angular momentum of the system after the clay sticks compare to the angular momentum of the system before the clay sticks, and what is an explanation for the comparison?

![Diagram](https://nerd-notes.com/wp-content/uploads/2024/03/Screenshot-2024-03-28-at-4.23.24-PM-245x300.png)

- **A.** It is the same because there is no external torque acting on the system.
- **B.** It is greater because the rotating mass increases, which increases the rotational inertia.
- **C.** It is less because the speed of the disk decreases when the clay sticks to it.
- **D.** It is less because the angular momentum of the clay opposes that of the disk.

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/29490/*