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Photon Energy Equation:
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Photon energy is the energy carried by a single photon, which is directly proportional to its electromagnetic frequency and inversely proportional to its wavelength. This relationship is fundamental to quantum mechanics and photonics.
The calculator uses the photon energy equation:
Where:
Explanation: The equation shows that shorter wavelengths correspond to higher energy photons, while longer wavelengths correspond to lower energy photons.
Details: Calculating photon energy is essential in various fields including spectroscopy, quantum mechanics, photochemistry, and optical communications. It helps determine the energy required for electronic transitions and chemical reactions.
Tips: Enter the wavelength in meters. For common light wavelengths, remember that visible light ranges from approximately 380-750 nanometers (3.8×10⁻⁷ to 7.5×10⁻⁷ m).
Q1: What is Planck's constant?
A: Planck's constant (h) is a fundamental physical constant that relates the energy of a photon to its frequency. Its value is approximately 6.626 × 10⁻³⁴ joule-seconds.
Q2: How is photon energy related to frequency?
A: Photon energy is directly proportional to frequency: E = hf, where f is the frequency. Since c = fλ, we can also express it as E = hc/λ.
Q3: What are typical photon energy values?
A: Photon energies vary widely. Radio wave photons have energies around 10⁻⁹ eV, visible light photons around 1.8-3.1 eV, while gamma ray photons can have energies of millions of eV.
Q4: Can I calculate energy in electronvolts instead of joules?
A: Yes, to convert joules to electronvolts, divide by 1.602 × 10⁻¹⁹ (since 1 eV = 1.602 × 10⁻¹⁹ J).
Q5: Why is photon energy important in solar cells?
A: Solar cells require photons with sufficient energy to excite electrons across the band gap of the semiconductor material. Photons with energy below this threshold cannot generate electricity.