Physics Course/Light

Sources of Light

Light comes from difference sources .

Light from Stars (the Sun), from the Moon (reflection).
  • Light from Fire.
A chemical reaction between flammable and combustible materials . Example(s): a Candle's Light, a Matches' Light.
  • Light from Electric Discharge
Light from thunder.
  • Light from Biolife
Bioluminesence, a chemical reaction. Example(s): Fireflies, Certain Bacteria
  • Electromagnetic Radiated Lights
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 Radiated 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


Last modified on 17 December 2013, at 15:35