Tangential speed at a fixed radius equals radius times angular speed.
Difficulty
Intermediate
Read time
5 min
Prerequisites
Basic algebra, consistent units, and the stated model assumptions
Source
OpenStax, College Physics 2e, §6.1 (Paul Peter Urone and Roger Hinrichs)OpenFormulaGraph equation reference; FormuLab adaptation details and license are provided below.
Adapted from OpenFormulaGraph, under CC BY 4.0.
FormuLab adapted wording, notation, applicability conditions and topic placement, and expanded the numerical check into a worked example.
Tangential speed at a fixed radius equals radius times angular speed. Points farther from the axis move faster even though they share the same angular speed.
| Symbol | Meaning | Units |
|---|---|---|
| Tangential speed | ||
| Radius | ||
| Angular speed |
Relate rim speed to shaft angular speed.
Compare tangential speeds at different radii.
A point is 2 m from a rotation axis turning at 3 rad/s. Find its tangential speed.
OpenFormulaGraph equation reference; FormuLab adaptation details and license are provided below.
Adapted from OpenFormulaGraph, under CC BY 4.0.
FormuLab adapted wording, notation, applicability conditions and topic placement, and expanded the numerical check into a worked example.
Assumptions
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