Static friction adjusts to prevent relative sliding up to a limiting magnitude.
Difficulty
Beginner
Read time
5 min
Prerequisites
Basic algebra and consistent SI units
Source
OpenStax, College Physics 2e, §5.1 (Paul Peter Urone and Roger Hinrichs)Textbook reference retained from the OpenFormulaGraph dataset; adaptation credits and license are provided below.
Adapted from OpenFormulaGraph, under CC BY 4.0.
FormuLab adapted the notation, explanations, assumptions, and topic placement, and expanded the numerical check into a worked example.
Static friction adjusts to prevent relative sliding up to a limiting magnitude. This equation gives that limit, not the friction force in every stationary contact. The actual force follows from equilibrium and may be smaller.
| Symbol | Meaning | Units |
|---|---|---|
| Maximum static friction magnitude | ||
| Static friction coefficient | ||
| Normal contact-force magnitude |
Compare the required friction with its available limit.
Estimate whether a contact can remain stationary.
A stationary contact has N = 20.0 N and μ_s = 0.500. Find its maximum available static friction.
Textbook reference retained from the OpenFormulaGraph dataset; adaptation credits and license are provided below.
Adapted from OpenFormulaGraph, under CC BY 4.0.
FormuLab adapted the notation, explanations, assumptions, and topic placement, and expanded the numerical check into a worked example.
Assumptions
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