---
title: "A runner is moving at \\( 4 \\) \\( \\text{m/s} \\). She is opposed by magic in the form of air resistance, which exerts a constant \\( 20 \\) \\( \\text{Newtons} \\) force in the direction opposite her velocity. At what rate is she using energy to remain at constant velocity?"
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/84445/"
date_modified: "2025-03-27T02:04:58+00:00"
---

# A runner is moving at \( 4 \) \( \text{m/s} \). She is opposed by magic in the form of air resistance, which exerts a constant \( 20 \) \( \text{Newtons} \) force in the direction opposite her velocity. At what rate is she using energy to remain at constant velocity?

A runner is moving at \( 4 \) \( \text{m/s} \). She is opposed by magic in the form of air resistance, which exerts a constant \( 20 \) \( \text{Newtons} \) force in the direction opposite her velocity. At what rate is she using energy to remain at constant velocity?

- **A.** \( 5 \) \( \text{W} \)
- **B.** \( 20 \) \( \text{W} \)
- **C.** \( 40 \) \( \text{W} \)
- **D.** \( 80 \) \( \text{W} \)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/84445/*