Fermi impulsion

Note.- We sometimes come across the term Fermi impulsion, which is the maximum value of the impulsion of the free electrons at the temperature of absolute zero. To find the expression of it, we only need to write ... 

In relation with the Fermi energy and wave vector one can introduces also other measures of interest, as Fermi velocity v calling the relation between velocity v and impulse p through the mass m,v = mp, so having... 

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