How Does Quantum Mechanics Calculate Proton Interactions at High Temperatures?

AI Thread Summary
The discussion focuses on calculating the distance of closest approach between two protons, one at rest and the other with kinetic energy equivalent to that of a proton in a gas at 10^7 K. The approach involves equating kinetic and potential energy, but there is a misapplication of gravitational potential energy instead of electric potential energy. The de Broglie wavelength is calculated using Planck's constant and momentum derived from the kinetic energy, with a comparison made to the distance of closest approach. Additionally, the calculations are repeated for a proton with ten times the initial kinetic energy. The importance of using the correct potential energy for charged particles is emphasized.
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Homework Statement



What is the distance of closest approach between two protons if one is at rest
and the other approaches from really far away with an initial kinetic energy equal to the
average kinetic energy of a proton in a 107K gas? (b) What is the de Broglie
wavelength of a proton with the above kinetic energy? The de Broglie wavelength
is h=p where h is Planck's constant and p is the momentum of the particle. How
does the wavelength compare with the distance of closest approach? (c) Repeat the
above calculations for a proton with 10 times the energy.

Homework Equations





The Attempt at a Solution



for a). I assume you must do an energy relationship so

E1 = E2

1/2mv^2 = 3/2kT = K ==> mv^2 = 3kT ===> v = 3kT/Mp

1/2mv^2 = mgh

h = 1/2gv^2 = 1/(2g(3kt/Mp)^2) = some value... is this the correct approach?

b) the second part using 3kt = mv^2 ===> solve for v then mv is the P = momentum

Lambda = h/p = some value is this correct?

c) just compare values

d) same thing with 10 x the kinetic energy I suppose
 
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So in part a, you seem to have a "g" floating around. It looks like you assumed the final potential energy is gravitational. The final potential energy should be for electric charges, neglect gravity.
 
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