Peak Trough Amplitude Wavelength () (in meters) Frequency measured in Hertz: (Hz): cycles

per second

Speed of a wave = wavelength * frequency

v=f

Increased frequency has increased energy for Electromagnetic waves:

◦ Speed = 3.0x108 m/s (speed of light)◦ c = 3.0x108 m/s

RabidMonkeysInVioletUnderpantseXterminateGibbons

Radio WavesMicrowavesInfraredVisual LightUltra VioletX-RayGamma Ray

Large

Small

Small f

Large f

Low NRG

High NRG

Range of wavelengths in the visible spectrum7.5 x 10-7 m 4 x 10-7 m750nm 400nm

R O Y G B I V

Colour Wavelength Interval Frequency range(Hz)

Red ~ 630–750 nm 4.76 - 4 (1014)

Orange ~ 590–630 nm 5.09 – 4.76 (1014)

Yellow ~ 560–590 nm 5.36 – 5.08 (1014)

Green ~ 490–560 nm 6.12 – 5.36 (1014)

Blue ~ 450–490 nm 6.67 – 6.12 (1014)

Indigo ~ 435–450 nm 6.90 – 6.67 (1014)

Violet ~ 400–450 nm 7.5 – 6.67 (1014)

All colours added together

Continuous Colour Spectrum

A line spectrum consists of distinct bright lines appearing on a dark background that occur in different parts of the visible spectrum.

An atom excited by addition of energy (heat) will send off electron(s) from its orbital. As the electron returns, it emits electromagnetic waves, and can be seen as coloured light.

P.143

http://www.lon-capa.org/~mmp/kap29/Bohr/app.htm

http://physics.gac.edu/~chuck/PRENHALL/Chapter%2031/AABXTEI0.html

http://mo-www.harvard.edu/Java/MiniSpectroscopy.html

http://jersey.uoregon.edu/vlab/elements/Elements.html

http://www.colorado.edu/physics/2000/quantumzone/index.html