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Waves or Particles?

Planck's Idea Used at Last!

 

The energy of the photons 'E' is given by

E = h f,

where 'h' is Planck's constant and 'f' is the frequency of the light.

 

Einstein's explanation of the photoelectric effect assumes that the photons of light transfer their energy to the electrons in the metal target.

The photons penetrate the surface of the metal and transfer some of their energy to the electrons which are subsequently ejected from the metal. This only happens for photons above a certain energy as there is a minimum energy requirement for electrons to be able to leave the metal. Einstein received the Nobel Prize in Physics in 1921 for this work. The photoelectric effect was studied in detail by Robert Millikan who also measured the charge of the electron – he was awarded the Nobel Prize in Physics in 1923.

 

Related Laureates

 The Nobel Prize in Physics 1923 - Robert Andrews Millikan »  The Nobel Prize in Physics 1921 - Albert Einstein »  
 



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