The electromagnetic spectrum | Middle school physics | Khan Academy

Understanding Light as a Wave00:00:00

Light behaves like a wave, defined by speed, frequency, wavelength, and amplitude. Unlike water or sound waves that require physical mediums, light waves propagate through the oscillation of electric and magnetic fields, allowing them to travel through a vacuum.

Defining Color and Brightness00:04:15

The color of light is determined by its frequency; lower frequencies appear red, while higher frequencies appear blue. Brightness is controlled by the wave's amplitude, where larger amplitudes result in more intense light.

The Electromagnetic Spectrum00:06:02

Visible light is only a small portion of the electromagnetic spectrum. The spectrum spans from long-wavelength radio waves and microwaves to infrared, visible light, ultraviolet rays, X-rays, and high-frequency gamma rays, each with unique properties and applications.