The total energy of a massive particle includes both rest energy and kinetic energy.
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.
The total energy of a massive particle includes both rest energy and kinetic energy. Subtracting mc² from this result gives its relativistic kinetic energy.
| Symbol | Meaning | Units |
|---|---|---|
| Energy (relativistic total) | ||
| Invariant (rest) mass | ||
| Speed of Light | ||
| Velocity |
Find total energy including rest energy.
Subtract rest energy to obtain relativistic kinetic energy.
A particle of rest mass 0.00100 kg moves at the listed speed. Find its relativistic total energy.
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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