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Physics Course/Light

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Sources of Light

Light comes from difference sources .

Light from Stars (the Sun), from the Moon (reflection).
A chemical reaction between flammable and combustible materials . Example(s): a Candle's Light, a Matches' Light.
Light from thunder.
Bioluminesence, a chemical reaction. Example(s): Fireflies, Certain Bacteria
Matter Absorbs Electric Energy until one point in time it no longer absorb Electric Energy instead it converts Electric Energy into Radiated Electromagnetic Light.
Electric's Conductor when conducts current release Heat and radiate Light.

Characteristics of Light

  • Light travels as a wave at a constant speed C = 3 x 108 m/s in vacuum
  • Light shines on an object will leave objects' image
  • The absorption of Light Energy depend on matter material's Thickness and Color .
Thick Clothes are easy to dry under the sun light . Dark Clothes are easy to dry under the sun light
  • Light Wave from different sources travel in the same medium can interfere with each other to produce different kinds of Light's Interference . No Light, when light waves interfere constructively . Bright Light when light waves interfere Destructively
  • Light Wave can be reflected back into the medium that it comes from and could be interfere with other wave lights in the medium to produce Interference
  • Light Decomposed into Six lights of six colors Red , Orange , Yellow , Green , Blue , Violet when it travels through a crystal medium . For example Rainbow in the sky after the rain . Light passing through Prism
  • Color of light can be produced from three primaries colors namely Red Green Blue commonly refer to as RGB by mixing them in percentage
  • Light that the eyes perceive are in the frequency length of that has wavelength 400 - 700 nm
  • According to Kaluza-Klein Theory, it may be a ripple in a five dimensional space-time fabric

Light and Matter

Reference