Photon Energy (Planck)
Energy of a photon is proportional to its frequency. Foundation of quantum theory.
Variables
Derivation
Introduced by Planck to explain blackbody radiation.
Your notes
Constants in this formula
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- h = 6.626 070 15 × 10⁻³⁴ J·s (Planck constant)
- f = 2 Hz (Frequency)
Result: E = 1.325214 × 10⁻³³ J
Other modern physics formulas with the same quantities
- Photon Momentum (Quantum Mechanics) shares Planck constant, Wavelength, Photon energy, Speed of light
- Stopping Potential (Quantum Mechanics) shares Planck constant, Frequency
- Compton Scattering (Quantum Mechanics) shares Planck constant, Speed of light
- Particle in a Box Energy Levels (Quantum Mechanics) shares Planck constant
- Photoelectric Threshold Frequency (Quantum Mechanics) shares Planck constant
- Bragg's Law (Quantum Mechanics) shares Wavelength
Where this formula is listed
- Modern Physics formulas, under Quantum Mechanics, alongside Heisenberg Uncertainty Principle, Energy-Time Uncertainty, Time-Dependent Schrödinger Equation, Fermi Energy and Electron Wavelength (Accelerated).
- In the modern physics list it comes after Relativity of Simultaneity and before Photoelectric Effect.
- Modern Physics formula sheet, one of 41 formulas printed with symbol keys and SI units.
- The full formula index, grouped by category and topic.
Common questions
What is the Photon Energy (Planck) formula?
Photon Energy (Planck) is written E = hf = hc/λ. Energy of a photon is proportional to its frequency. Foundation of quantum theory. It belongs to Modern Physics, under Quantum Mechanics.
What are the units in E = hf = hc/λ?
In SI units, E is photon energy, measured in J; h is planck constant, measured in J·s; f is frequency, measured in Hz; c is speed of light, measured in m/s; λ is wavelength, measured in m.
How is the Photon Energy (Planck) formula derived?
Introduced by Planck to explain blackbody radiation. The result is E = hf = hc/λ.