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Wave - Particle Duality j

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					Wave - Particle Duality
Evidence ;

Wave Model      Particle Model
 Diffraction    Photoelectric Effect
 Interference   Spectrometry
 Polarisation
 Refraction
 Reflection


=> QUANTUM THEORY OF RADIATION
Duality

z ALL physical entities may be described as
  either WAVES or PARTICLES       (Duality)
z Linked by two equations ;
     E = hf
     p = h/l              (De Broglie equation)
       E, p - particle phenomena
       f, l - wave phenomena
       as predicted by Einstein
                         Special Theory of Relativity,
       h = Planck constant = 6.6 x 10-34 Js
Some more Maths

z consider a photon ;
p = h/l,      E = hf,        c = fl
p = h/l = hf/c = E/c
=> E = pc
but, p = mc       (momentum = mass x velocity)

          => E = mc2
What does it mean ?

z When a photon is considered as a
  particle, its mass may be taken as
  equal to ;
z m = E/c2 = hf/c2
z this ‘mass/energy equivalence’ is
  only significant in nuclear physics.

				
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posted:3/19/2014
language:English
pages:7