1. What is the Energy of Light Equation?

The energy of light equation \( E = \frac{hc}{\lambda} \) calculates the energy of a photon based on its wavelength. This fundamental equation in quantum mechanics relates the particle and wave properties of light.

2. How Does the Calculator Work?

The calculator uses the energy equation:

Where:

• \( E \) — Energy in joules (J)
• \( h \) — Planck's constant (6.626 × 10⁻³⁴ J·s)
• \( c \) — Speed of light (3 × 10⁸ m/s)
• \( \lambda \) — Wavelength in meters (m)

Explanation: The equation shows that energy is inversely proportional to wavelength - shorter wavelengths correspond to higher energy photons.

3. Importance of Energy Calculation

Details: Calculating photon energy is essential in quantum mechanics, spectroscopy, photochemistry, and understanding light-matter interactions. It helps determine if light has sufficient energy to cause electronic transitions or chemical reactions.

4. Using the Calculator

Tips: Enter the wavelength in meters. The value must be greater than zero. For very small wavelengths (e.g., visible light around 500 nm), use scientific notation (5e-7 for 500 nm).

5. Frequently Asked Questions (FAQ)

Q1: What is Planck's constant?
A: Planck's constant (6.626 × 10⁻³⁴ J·s) is a fundamental physical constant that relates the energy of a photon to its frequency.

Q2: Can I use nanometers instead of meters?
A: Yes, but you must convert nanometers to meters by multiplying by 10⁻⁹ before calculation.

Q3: What is the typical energy range for visible light?
A: Visible light (400-700 nm) has energies ranging from approximately 1.8 to 3.1 eV (2.9 × 10⁻¹⁹ to 5.0 × 10⁻¹⁹ J).

Q4: How does this relate to photon frequency?
A: The equation \( E = hf \) is equivalent, where f is frequency. Since \( c = f\lambda \), the two forms are interchangeable.

Q5: Why are the energy values so small?
A: Individual photons carry very small amounts of energy. One joule represents the energy of about 10¹⁸ visible light photons.