How to Calculate Photon Energy
What is Photon Energy?
Photon energy is the energy carried by a single light photon. Higher frequency (shorter wavelength) = more energy per photon. X-rays carry thousands of times more energy than visible light.
Formula
- E
- Photon energy (J or eV)
- h
- Planck constant (6.626×10⁻³⁴ J·s)
- f
- Frequency (Hz)
- λ
- Wavelength (m)
- c
- Speed of light (3×10⁸ m/s)
Step-by-Step Guide
- 1E = hf (Planck's equation)
- 2E = hc/λ (from wave equation c = fλ)
- 3h = 6.626×10⁻³⁴ J·s; c = 3×10⁸ m/s
- 4Convert to eV: 1 eV = 1.6×10⁻¹⁹ J
Worked Examples
Frequently Asked Questions
What is Photon Energy?
Photon energy is the energy carried by a single light photon. Higher frequency (shorter wavelength) = more energy per photon
How accurate is the Photon Energy calculator?
The calculator uses the standard published formula for photon energy. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.
What units does the Photon Energy calculator use?
This calculator works with inches. You can enter values in the units shown — the calculator handles all conversions internally.
What formula does the Photon Energy calculator use?
The core formula is: E = hf (Planck\. Each step in the calculation is shown so you can verify the result manually.
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