Rest energy is associated with a system’s invariant mass.
Difficulty
Intermediate
Read time
5 min
Prerequisites
Basic algebra, consistent units, and the stated model assumptions
Source
OpenStax, College Physics 2e, §28.6 (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. The textbook section reference was corrected.
Rest energy is associated with a system’s invariant mass. It is part of relativistic total energy and should not be confused with kinetic energy or automatically available useful energy.
| Symbol | Meaning | Units |
|---|---|---|
| Energy (rest mass) | ||
| Invariant (rest) mass | ||
| Speed of Light |
Relate invariant mass to its associated energy.
Relate a system’s rest-mass change to an energy difference.
Find the rest energy associated with mass 0.00100 kg using the listed speed of light.
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. The textbook section reference was corrected.
Assumptions
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