Fri June 08, 2012 By: Tabish


Expert Reply
Fri June 08, 2012
a photon is a discrete bundle (or quantum) of electromagnetic (or light) energy. Photons are always in motion and, in a vacuum, have a constant speed of light to all observers, at the vacuum speed of light (more commonly just called the speed of light) of c = 2.998 x 108 m/s.
Like all elementary particles, photons are currently best explained by quantum  mechanics,and exhibit wave particle duality, exhibiting properties of both wave  and  particles. The modern concept of the photon was developed gradually by einstein to explain experimental observations that did not fit the classical wave  model of light.
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