A photon’s energy is proportional to its frequency.
Difficulty
Intermediate
Read time
5 min
Prerequisites
Basic algebra, consistent units, and the stated model assumptions
Source
OpenStax, College Physics 2e, §29.3 (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.
A photon’s energy is proportional to its frequency. Frequency, rather than the wavelength inside a refracting medium, determines this energy directly.
| Symbol | Meaning | Units |
|---|---|---|
| Energy (photon) | ||
| Planck's Constant | ||
| Frequency |
Find the energy of one photon.
Compare photon energies at different frequencies.
Find the energy of one photon with frequency 5.00 × 10¹⁴ Hz using the listed Planck constant.
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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