​What is a wave?

​A wave is a disturbance that carries energy from place to place. 

A wave does NOT carry matter with it! It just moves the matter as it goes through it.

Parts of a transverse wave:

Crest: the highest point of a transverse wave.

Trough: the lowest point of a transverse wave.

Parts of a transverse wave:

Wavelength: the distant between two crests or two troughs.

Amplitude: the distance between the middle horizontal line and the highest point or between the middle line and the lowest point.

Wavelength:

Parts of a longitudinal wave:

Parts of a longitudinal wave:

Compression: the parts of the wave where the loops are close together.

Parts of a longitudinal wave:

Rarefaction: the parts of the wave where the loops are spread-out.

Parts of a longitudinal wave:

Wavelength: the distance between two compressions.

​Types of wave

Electromagnetic (EM) waves: Do NOT require a medium to travel.​

​Sound can be reflected and produce ECHO

Visible light

(commonly referred to simply as light) is electromagnetic radiation that is visible to the human eye and is responsible for the sense of sight. Visible light has a wavelength in the range of about 380 nanometres to about 740 nm – between the invisible infrared, with longer wavelengths, and the invisible ultraviolet, with shorter wavelengths.

• Waves in visible range appear to us as a spectrum of colors.

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• ​Each color corresponds to a certain wavelength and frequency of light.

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• The wavelength and frequency of light determines its color.

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Light waves & color