(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Derive an expression for the total energy required to asemble a sphere of charge corresponding to a nucleus of atomic number Z and radius R. Assume the nucleus is a sphere of uniform volume charge density [tex]\rho[/tex]

2. Relevant equations

[tex]\rho[/tex] = mass / volume = 3Am / 4*pi*R^{3}

3. The attempt at a solution

I know the solution is U = 3k * (Ze)^{2}/ 5R, so I need to work on deriving this.

I also know that when an alpha particle collides with the nucleus, the initial kinetic energy is equal to the electrical potential energy of the system and is given by

.5mv^{2}= kq_{1}q_{2}/r = k(2e)(Ze)/d where d = 4kZe^{2}/ mv^{2}

Not sure how this helps though, but it seems to be in a relevant section in the textbook. There is also info on the binding energy, but it doesn't seem applicable in this case.

Any tips on how to approach the problem, please?

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# Homework Help: Nuclear Model - Expression for Total Energy [Modern Physics]

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