1. What is the Energy of Light Calculator?

Definition: This calculator computes the energy (\( E \)) of a single photon of light based on its wavelength (\( \lambda \)), using the Planck-Einstein relation.

Purpose: It is used in physics to determine the energy of photons in applications like spectroscopy, quantum mechanics, and photonics, aiding in understanding light-matter interactions.

2. How Does the Calculator Work?

The calculator uses the relationship:

Where:

• \( E \) — Energy of a photon (in various units)
• \( h \) — Planck's constant (\( 6.62607015 \times 10^{-34} \, \text{J·s} \))
• \( c \) — Speed of light (\( 299,792,458 \, \text{m/s} \))
• \( \lambda \) — Wavelength of the light

Explanation: Enter the wavelength of the light in the chosen units, and the calculator computes the energy of a single photon. Results are displayed with 5 decimal places, using scientific notation if the value exceeds 100,000 or is less than 0.0001. For the default input (\( \lambda = 500 \, \text{nm} \)), the calculated photon energy \( E \) is approximately 3.97606e-19 Joules.

3. Importance of Photon Energy

Details: Photon energy is a fundamental concept in quantum mechanics, describing the energy carried by a single photon of light. It is crucial for understanding phenomena like the photoelectric effect, laser technology, and the interaction of light with matter in scientific research.

4. Using the Calculator

Tips: Enter a positive value for the wavelength with up to 4 decimal places (step of 0.0001), ensuring \( \lambda \neq 0 \) to avoid division by zero, then click "Calculate." Results show the photon energy \( E \) in Joules, Electronvolts, Megaelectronvolts, Kilojoules, British Thermal Units, and Kilocalories. Values greater than 100,000 or less than 0.0001 are displayed in scientific notation with 5 decimal places. The default wavelength of 500 nm corresponds to green light in the visible spectrum.

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