Photon Energy Calculator
Calculate photon energy from frequency or wavelength using Planck's equation.
✨ Physics📐 E = hf = hc/λ
Frequency (Hz) or 0
Wavelength (m) or 0
Please enter valid values.
Formula & Reference
| Variable | Formula | Units |
|---|---|---|
| Photon Energy Calculator | E = hf = hc/λ | Joules / eV |
Step-by-Step Examples
Example 1
Green Light
Freq 6×10¹⁴ Hz.
- E = 6.626e-34 × 6e14 = 3.98e-19 J = 2.48 eV
✓ 3.98×10⁻¹⁹ J / 2.48 eV
Example 2
X-ray 1nm
Wavelength 1e-9 m.
- f = 3e17 Hz | E = 1.99e-16 J = 1,243 eV
✓ 1,243 eV
Example 3
AM Radio 1MHz
Freq 1e6 Hz.
- E = 6.626e-28 J — very low energy per photon
✓ 6.626×10⁻²⁸ J
Real-World Applications
Physics Students
Learn quantum mechanics with photon calculations.
Researchers
Calculate photon energies for spectroscopy.
Optics Engineers
Analyze light energy for laser and LED design.
Medical Physicists
Calculate X-ray and gamma ray energies.
Common Mistakes to Avoid
⚠️
Photon energy vs intensity
One X-ray photon can ionize an atom. Many radio photons cannot, regardless of total power. This is the photoelectric effect.
⚠️
eV vs Joules
1 eV = 1.602×10⁻¹⁹ J. Use eV for atomic/nuclear, J for larger scales.
Frequently Asked Questions
Planck's constant? ▾
h = 6.626×10⁻³⁴ J·s — fundamental quantum constant.
Color and photon energy? ▾
Higher frequency = higher energy = shorter wavelength. Violet (400nm, 3.1 eV) > red (700nm, 1.8 eV).
What is 1 eV? ▾
Energy given to an electron accelerated through 1 volt = 1.602×10⁻¹⁹ J.