Fermi Energy of 40P 50N Nucleus Sphere

[viviane363]

Homework Statement

I am wondering about something:
Calculate the Fermi energy for the neutrons confined to a nucleus with 40 protons and 50 neutrons which roughly forms a sphere of radius 4.6 10^(-15) m.

Homework Equations

the formula of the fermi Energy is EF= ((h-bar)^2*(3*pi^2*n)^(2/3))/2m
m:mass of electron, n = number density of electron

The Attempt at a Solution

Then, in the problem we are given protons and neutrons. Where does influence the formula? and where do we use the radius there is one relation that is n = N/V ( N= protons+Neutrons)
and V is the volume of the sphere.
is it right?
Also, do we use the mass of electron or the mass of proton = neutron this time?

 

[Welshy]

The mass should be of fermions in general - not just electrons. Same with the number density. And since protons and neutrons are fermions, you're equation should work.