PHYS 2004 Lecture Notes - Lecture 22: Black-Body Radiation, Photon, Work Function
1 Dec 2017
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Document Summary
Around 1900, max planck was able to predict the spectrum of blackbody radiation by assuming that atoms oscillating with frequency f could only have specific energy values. Planck"s constant is h = 6. 63 10 34 j s. In 1905, albert einstein suggested that the electromagnetic radiation itself is quantized! Einstein called each packet of energy a light quantum, with energy: Einstein was awarded the nobel prize not for his theory of relativity, but for his explanation of the photoelectric effect! Quanta of light energy were later given the name photons. Einstein framed three postulates about photons and their interaction with matter: light of frequency f consists of discrete quanta, each of energy e = hf. Each photon travels at the speed of light c: photons are emitted or absorbed on an all-or-nothing basis. A substance can only emit or absorb an integer number of photons.
