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Energy Formula:
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The equation E = h·c/λ calculates the energy of a photon from its wavelength, where h is Planck's constant, c is the speed of light, and λ is the wavelength. This fundamental physics equation relates the particle and wave properties of light.
The calculator uses the energy equation:
Where:
Explanation: The equation shows that energy is inversely proportional to wavelength - shorter wavelengths correspond to higher energy photons.
Details: Calculating photon energy is essential in quantum mechanics, spectroscopy, photochemistry, and understanding electromagnetic radiation across different wavelengths from radio waves to gamma rays.
Tips: Enter the wavelength in meters. For common measurements, remember: 1 nanometer = 10⁻⁹ meters, 1 micrometer = 10⁻⁶ meters. The wavelength must be greater than zero.
Q1: What are typical energy values for different wavelengths?
A: Visible light (400-700 nm) has energies around 3.1-1.8 eV (5.0-2.9×10⁻¹⁹ J), while X-rays have much higher energies around 10³-10⁶ eV.
Q2: Can I use other units for wavelength?
A: Yes, but you must convert to meters first. The calculator requires input in meters for proper calculation.
Q3: What is the relationship between energy and frequency?
A: Energy is also related to frequency by E = h·f, where f is frequency. Since c = λ·f, both equations are equivalent.
Q4: Why is the energy value so small?
A: Individual photons carry very small amounts of energy measured in joules, which is why we often use electronvolts (1 eV = 1.602×10⁻¹⁹ J) in quantum physics.
Q5: What are practical applications of this calculation?
A: This calculation is used in designing lasers, understanding atomic spectra, photoelectric effect studies, and various technologies including solar cells and medical imaging.