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Photon Energy Equation:
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The photon energy equation E = hc/λ calculates the energy of a single photon using Planck's constant (h), the speed of light (c), and the photon's wavelength (λ). This fundamental equation in quantum mechanics relates a photon's energy to its electromagnetic wavelength.
The calculator uses the photon energy equation:
Where:
Explanation: The equation shows that photon energy is inversely proportional to its wavelength - shorter wavelengths correspond to higher energy photons.
Details: Calculating photon energy is essential in various fields including quantum physics, spectroscopy, photochemistry, and optical engineering. It helps determine if a photon has sufficient energy to cause electronic transitions, chemical reactions, or other quantum phenomena.
Tips: Enter the wavelength in meters. For common wavelengths, remember that 1 nanometer = 10⁻⁹ meters. The wavelength must be greater than zero.
Q1: What are typical energy values for visible light photons?
A: Visible light photons (400-700 nm) have energies ranging from approximately 3.1 to 1.8 electronvolts (5.0 × 10⁻¹⁹ to 2.8 × 10⁻¹⁹ Joules).
Q2: How does photon energy relate to frequency?
A: Photon energy can also be calculated as E = hf, where f is frequency. This is equivalent to E = hc/λ since c = fλ.
Q3: Why is Planck's constant so small?
A: Planck's constant is small because it relates energy to frequency at the quantum scale. Individual photons carry very small amounts of energy in macroscopic terms.
Q4: Can this equation be used for all electromagnetic radiation?
A: Yes, the equation applies to all photons across the electromagnetic spectrum, from radio waves to gamma rays.
Q5: How is photon energy measured experimentally?
A: Photon energy can be measured through various methods including photoelectric effect experiments, spectroscopy techniques, and calorimetric measurements.