Quantum Physics: electron within the nucleus.

AI Thread Summary
The discussion focuses on calculating the smallest allowed energy of an electron confined within an atomic nucleus, specifically one with a diameter of 1.4x10^-14 meters. Participants clarify that the problem does not pertain to the Bohr model, as it involves interactions between protons and neutrons. The Uncertainty Principle is suggested as a method to determine the electron's energy, using the nucleus size to find momentum and kinetic energy. One participant arrives at an energy value of approximately 1995 MeV, indicating significant energy levels compared to typical nuclear binding energies. The conclusion emphasizes that the high energy suggests electrons are unlikely to be found within the nucleus.
frankR
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Calculate the smallest allowed energy of an electron were trapped inside an atomic nucleus of diameter 1.4x10^-14 meters. Compare this number with the several MeV of energy binding protons and neutrons inside the nucleus. On this basis, should we expect to find electrons within the nucleus?




I'm experiencing some confusion regarding what this statement is asking.

Do I assume that the question pertains to a one proton nucleus, under the Bohr model? However it states energies between protons and neutrons so the Bohr model must not pertain to the question.

I can find the electric potential of the electron if I know how many protons are contained within the nucleus. Do I use:

r = roA1/3 to find the number of protons?

Thereafter use U = k q1*q2/r to find the potential. Is this how this is done.

The correct answer should be 1900MeV.

Thanks
 
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I think it has nothing to do with protons.

I think they just want you to use a 'potential well'. Meaning V(r) = 0 if r <= R, and V(r) = [oo] if r > R.
 
Originally posted by frankR
Calculate the smallest allowed energy of an electron were trapped inside an atomic nucleus of diameter 1.4x10^-14 meters.

OK

Do I assume that the question pertains to a one proton nucleus, under the Bohr model? However it states energies between protons and neutrons so the Bohr model must not pertain to the question.

No, I think this is a simple exercise in using the Uncertainty Principle. You have a &Delta;x (the size of the nucleus). From that you can calculate a &Delta;p, which is the smallest allowed momentum. From that you can calculate the smallest allowed KE.
 
Tom: You're correct, I got 1995MeV.:smile:
 
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