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Physics of Waves
Properties of Light:
How does Light
Travel Through Space and Other Media
- light is a transverse wave
- light is an electromagnetic wave and travels in vacuum
(Descartes had proposed as medium the Ether -- proved to be wrong)
- light behaves as wave and as particle
(Einstein won the Nobel Prize
for explaining the photoelectric effect)
- speed of light 300,000 km/s
- frequency corresponds to color
- amplitude corresponds to brightness
Light Waves
How do we know that light is a wave?
Waves spread out either as wavefront or as spherical wave.
Wave character of light is established, when light
shows diffraction.
Examples for diffraction are the interference patterns
of a single, double or
multiple slit experiment.
Interference grating
is a phenomenon, when light
is diffracted by very many slits (more than 1000 per cm).
Then white light is decomposed into the spectral colors.
Watch light reflecting from a CD or DVD: you see many colors. The reason is that the tracks act like
a very many fine slits.
Other properties of light showing its wave character?
Refraction (light will bend)
---> Optics
Simulation to understand interference of waves:
Wave Interference
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Properties of Light