---
title: "A block of mass \\(M\\) is placed on a rough ramp that makes an angle \\(\\theta\\) with the horizontal, where \\(\\theta > 45^{\\circ}\\). The coefficient of static friction between the block and the ramp is \\(\\mu_s\\). When the block is released from rest, it remains stationary on the ramp. Which of the following is a correct expression for the magnitude of the static friction force \\(f_s\\) exerted on the block by the ramp?"
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url: "https://nerd-notes.com/ubq/109776/"
date_modified: "2026-03-26T05:49:52+00:00"
---

# A block of mass \(M\) is placed on a rough ramp that makes an angle \(\theta\) with the horizontal, where \(\theta > 45^{\circ}\). The coefficient of static friction between the block and the ramp is \(\mu_s\). When the block is released from rest, it remains stationary on the ramp. Which of the following is a correct expression for the magnitude of the static friction force \(f_s\) exerted on the block by the ramp?

A block of mass \(M\) is placed on a rough ramp that makes an angle \(\theta\) with the horizontal, where \(\theta > 45^{\circ}\). The coefficient of static friction between the block and the ramp is \(\mu_s\). When the block is released from rest, it remains stationary on the ramp. Which of the following is a correct expression for the magnitude of the static friction force \(f_s\) exerted on the block by the ramp?

![A block of mass M is at rest on a ramp inclined at an angle theta. A downward vector labeled Mg represents gravity. The ramp surface is drawn with cross-hatching to indicate it is rough. The angle theta is shown between the horizontal ground and the ramp surface, appearing visibly steeper than 45 degrees.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-1-1774504192-Hnv5lc.jpg)

- **A.** \(f_s = \mu_s M g \cos\theta\)
- **B.** \(f_s = M g \sin\theta\)
- **C.** \(f_s = M g \cos\theta\)
- **D.** \(f_s = \mu_s M g \sin\theta\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/109776/*