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Summarise thephoton pictureof electromagneticradiation . |
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Answer» SOLUTION :We can summarise the PHOTON picture of electromagneticradiation as follows . (1) In interaction of radiation with matter , radiationbehaves as if it is made up of particles called photons . (2) Eachphoton has ENERGY E `E[(=hv),(=(hc)/(lambda))]` and momentum P ` [ (=(hv)/c)/(=h/lambda)]` and speed c, the speed of light . (3 ) By increasing the density of lightof given wave length , there is only an increases in thenumberof photons per second crossing a given area , with each photon having the same energy . Thus , energy is independentof intensityof radiation . (4 ) Photons are not deflectedby electric and magnetic field . This showsthatphotons are electricallyneutral . (5 ) In a photon - particlecollision ( such as photo - electron collision ) , the energyand momentumare CONSERVED . However the numberof photonsmay not be conservedin a collision . One photon may be absorbedor a newphoton may be created . (6 ) The rest mass of photonis zero. According to theory of relativity , the massof moving particle is given by m = `(m_(0))/(sqrt(1-(v^(2))/(c^(2))))`wherev is VELOCITY of particle and c is velocityof light . |
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