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Energy-Wavelength Equation:
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The energy-wavelength equation (E = hc/λ) describes the relationship between the energy of a photon and its wavelength, where h is Planck's constant and c is the speed of light. This fundamental equation in quantum mechanics allows calculation of photon energy from its wavelength.
The calculator uses the energy-wavelength 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 spectroscopy, photochemistry, quantum physics, and optical engineering. It helps determine if a photon has sufficient energy to excite electrons or break chemical bonds.
Tips: Enter 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 are typical energy values for visible light?
A: Visible light photons have energies ranging from approximately 1.65-3.26 electronvolts (2.64×10⁻¹⁹ to 5.23×10⁻¹⁹ Joules).
Q2: How does this relate to the electromagnetic spectrum?
A: The equation applies to all electromagnetic radiation, from radio waves (low energy, long wavelength) to gamma rays (high energy, short wavelength).
Q3: Can I calculate energy in electronvolts instead of Joules?
A: Yes, divide the result in Joules by 1.602×10⁻¹⁹ to convert to electronvolts (eV), which is often more convenient for atomic-scale calculations.
Q4: Why is the energy inversely proportional to wavelength?
A: This inverse relationship comes from the wave-particle duality of light, where shorter wavelengths correspond to higher frequency oscillations and thus higher energy photons.
Q5: What are the limitations of this equation?
A: The equation is exact for individual photons in vacuum but doesn't account for medium effects (where speed of light changes) or quantum field effects at extremely high energies.