Tue September 10, 2013 By: Prateek Dubey

What is Planck's quantum theory

Expert Reply
Hanisha Vyas
Tue September 10, 2013
Max Plank in 1901 , gave a new revolutionary theory known as Quantum theory of radiation.
Main features of this theory are :
  1. radiant energy is not emitted or absorbed continously but discontinously in the form of small packets of energy called Quanta. Each quanta is associated with a definite amount of energy .
  2. E is directly proportional to frequency of light,
         E=hv  where h is known as planks constant.  h= 6.63x10-34 Js
     3.  The total amount of energy emitted or absorbed by the body will be some whole no. multiple of quantum ,i.e,
           E=nhv , where n is an integer such as 1, 2, 3, ....
 Since, the frequency , wavelength ?, and speed of light c are related by ?? = c, the Planck relation for a photon can also be expressed as

The above equation leads to another relationship involving the Planck constant.

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