---
title: "A coffee cup on the dashboard of a car slides forward when the driver decelerates from \\(45 \\dfrac{\\text{km}}{\\text{hr}}\\) to rest in \\(3.5 \\, \\text{s}\\) or less. What is the coefficient of static friction between the cup and the dash? Assume the road and the dashboard are completely horizontal."
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url: "https://nerd-notes.com/ubq/55298/"
date_modified: "2025-09-15T03:57:50+00:00"
---

# A coffee cup on the dashboard of a car slides forward when the driver decelerates from \(45 \dfrac{\text{km}}{\text{hr}}\) to rest in \(3.5 \, \text{s}\) or less. What is the coefficient of static friction between the cup and the dash? Assume the road and the dashboard are completely horizontal.

A coffee cup on the dashboard of a car slides forward when the driver decelerates from \(45 ~ \frac{\text{km}}{\text{hr}}\) to rest in \(3.5 \, \text{s}\) or less. What is the coefficient of static friction between the cup and the dash? Assume the road and the dashboard are completely horizontal.

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/55298/*