Can anyone help me to find an approximation to the size of a He atom at very low temperature (10^(-9)K)?(adsbygoogle = window.adsbygoogle || []).push({});

My attempt:

At this very low temperature all electrons will be in the ground state, thus using the equipartition theorem:

[tex] 1/2kT = h*c/lambda [/tex]

now, for the zero point energy, lambda is 1/2 the diameter of the Helium atom.

However, this approach does not yield the correct answer.

I have had a look at several textbooks, but couldn't find any hints in there.

Thanks a lot for your help!

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# Homework Help: Size of He atom at 10^(-9)K

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