---
title: "Two identical blocks are connected to the opposite ends of a compressed spring. The blocks initially slide together on a frictionless surface with velocity \\( v \\) to the right. The spring is then released by remote control. At some later instant, the left block is moving at \\( \\frac{v}{2} \\) to the left, and the other block is moving to the right. What is the speed of the center of mass of the system at that instant?"
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/82885/"
date_modified: "2025-03-18T06:58:36+00:00"
---

# Two identical blocks are connected to the opposite ends of a compressed spring. The blocks initially slide together on a frictionless surface with velocity \( v \) to the right. The spring is then released by remote control. At some later instant, the left block is moving at \( \frac{v}{2} \) to the left, and the other block is moving to the right. What is the speed of the center of mass of the system at that instant?

Two identical blocks are connected to the opposite ends of a compressed spring. The blocks initially slide together on a frictionless surface with velocity \( v \) to the right. The spring is then released by remote control. At some later instant, the left block is moving at \( \frac{v}{2} \) to the left, and the other block is moving to the right. What is the speed of the center of mass of the system at that instant?

- **A.** \[ \frac{5v}{2} \]
- **B.** \[ \frac{3v}{2} \]
- **C.** \( v \)
- **D.** \( \frac{v}{2} \)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/82885/*