- Light is defined in physics as an electromagnetic wave that has a wavelength between 380 and 780 nanometers. That's the part of the electromagnetic radiation that we humans can see. (1 nanometer = 0.000000001 meters)
- Electric and magnetic fields create a light particle, a so-called photon, which moves at the speed of light (300,000 kilometers per second) and has wavelength-dependent energy.
- E = hc / [lambda] with E = energy, h = plank's constant of action, c = speed of light and [lambda] = wavelength
- The shorter the wavelength, the higher the energy of the electromagnetic radiation.
- The following picture shows the visible light spectrum:
Image Source: en.wikipedia.org/wiki/Visible_spectrum
Link with Wikipedia icon: en.wikipedia.org/wiki/Light