I'm having some difficulty in working with units of mass at the quantum level. This difficulty most clearly manifests itself when I'm doing a Compton scattering problem.(adsbygoogle = window.adsbygoogle || []).push({});

Recall that Compton scattering is given by

[tex]\Delta \lambda =\frac{h}{m_{e}c}(1-cos(\theta ))[/tex]

and that the rest mass of an electron is 5.11 x 10^5 eV/c^2

My confusion seems to come about in the denominator. I find myself unsure of whether to multiply by c, c^2, or maybe something else entirely. In any case, for my problem, I keep getting the wrong answer, regardless of my method of attack.

If anyone could shed any insight on my problem, and also give me a big picture of relativistic units (i.e., here is how to handle relativistic units in calculations), it would be very much appreciated.

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# Difficulty with relativistic units, eV/c^2

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