I'm confused about how can I obtain this equation:(adsbygoogle = window.adsbygoogle || []).push({});

[tex]K=\frac{(cp)^{2}}{2m_{0}c^{2}}=\frac{h^{2}}{2m_{0}\lambda^{2}}[/tex]

being K the Kinetic energy, p the momentum andlambdathe wavelenght.

It's related with the energy of an electrons beam, and I don't know how to obtain it from the equations that I know so far (basically, E = hf = K + mc^2, withfthe frequency)

It's a really unhappy business :S

Thank you!

(Edit: Sorry about not have used the template, my question this time just not fit in it)

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# Homework Help: Where this equation comes from?

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