Light and ColorSpeed, Wavelength, Color

And

Human Perception

The Speed of LightFrequency and Wavelength

In a vacuum electromagnetic waves move at

C = 3 x 10⁸ m/sIt moves slower in a medium

The distance from one wave’s crest to the next is called its wavelength (λ).

The number waves that go by in a second is its frequency (f, measured: crests/s or hertz ‘hz’)

The electro-magnetic waves that our eyes can detect have wavelengths between 400 to 700 nanometers

We call it “Visible Light”Wavelength and Frequency are

inversely related by:c = f λ

Thus Visible Light is also between the frequencies of 7.5 - 4.3 x 10¹⁶ Hz

A Color is the human perception of a specific frequency of light.

Red is the lowest frequency color wavelength: 700 nm

Violet is the highest frequencywavelength 400 nm

The order from lowest to highest frequency is: Red, Orange, Yellow, Green, Blue, Indigo, and Violet

or“ROY G. BIV”

White Light and the Spectrum

White Light is the combination of all colors.

Black is no colors

White light can be split into all the colors…a Spectrum

This can be done using a prism, ice crystal or a drop of water