LIGHT ILLUMINATED!

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LIGHT ILLUMINATED!
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Properties of Waves
crest
trough
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Properties of Waves
Wavelength (length/cycle)
crest
trough
Wavelength the length of one complete cycle
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Properties of Waves
Wavelength (length/cycle)
crest
Amplitude
trough
Amplitude 1/2 height between trough and crest
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Properties of Waves
Wavelength (length/cycle)
crest
Amplitude
trough
Frequency the number of wavelengths that pass a
point in a unit of time. (The shorter the
wavelength, the higher the frequency)
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The Particle-Wave Theory

• Photon a bundle of energy
• A particle (photon) travels in a straight line in
  a wave-like fashion.

• Light is an electromagnetic wave.
• It is a transverse wave.
• The electric field is perpendicular to the
  magnetic field.
• All electromagnetic waves travel at the same
  speed. The speed of light 300 million m/s or
  186,300 mi/s.

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http//www.astronomynotes.com/light/s2.htm
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Electromagnetic waves are characterized by their
wavelength
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Small wavelength 10-12 m
Gamma rays X-rays Ultraviolet rays
Violet
Blue
Medium wavelength
Green
Yellow
Orange
Red
Infrared Radio waves
Large wavelength 100m-1000m
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Refraction Bending of waves due to a change in
speed. - The longer the wavelength, the less it
bends
White light has all the colors!
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Prisms

• A Prism is triangular object that separates white
  light into the spectrum colors.
• The white light is bent once it enters the prism,
  and the prism bends the different wavelengths of
  the white light. Out come the colors of the
  spectrum.
• The longer the wavelength (red) the less that it
  is bent, the shorter the wavelength (violet) the
  greater it is bent.
• Prisms are used for many different things
  Spectra Scopes and Binoculars.
• Isaac Newton was the first to show that When a
  second prism brings the different colors together
  again, white light is once more obtained.

Source http//www.phy6.org/stargaze/Sun4spec.htm
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When light strikes an object, it is either
transmitted, reflected, or absorbed. We see what
is reflected.
reflected
transmitted
absorbed