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Photon Energy Equation:
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The photon energy formula \( E = \frac{hc}{\lambda} \) calculates the energy of a 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 properties.
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 the energy levels of electromagnetic radiation across the spectrum from radio waves to gamma rays.
Tips: Enter the wavelength in meters. The value must be positive and non-zero. For common wavelengths, remember that 1 nanometer = 10⁻⁹ meters.
Q1: What are typical photon energy values?
A: Photon energies range from about 10⁻²⁵ J for radio waves to 10⁻¹³ J for gamma rays. Visible light photons have energies around 3-4 × 10⁻¹⁹ J.
Q2: Can I calculate energy in electronvolts instead of joules?
A: Yes, you can convert joules to electronvolts by dividing by 1.602 × 10⁻¹⁹ (since 1 eV = 1.602 × 10⁻¹⁹ J).
Q3: 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.
Q4: Why is Planck's constant so small?
A: Planck's constant is a fundamental physical constant that sets the scale for quantum effects. Its small value (6.626 × 10⁻³⁴ J·s) explains why quantum effects are not noticeable in everyday macroscopic objects.
Q5: What's the relationship between photon energy and color?
A: In visible light, higher energy photons correspond to violet/blue light (shorter wavelengths), while lower energy photons correspond to red light (longer wavelengths).