RU Links
Radford University
Department of Physics
RU Planetarium
RUSMART pages (weather)
Fall 2014 Classes & Info
PHYS 111
PHYS 330
My daily schedule
My C.V.
Summer jobs/internships
NSF REU Program (list of REU sites)
Other links
The Nucleus (resources for physics/astronomy undergrads)
PreHealth information
R.U.F.R.E.E.Z.I.N.G.
pics from the north pole trip
the picture from the trip
Simple 2liter water rocket
American Institute of Physics

Homework #9: Do not turn this in. I will post my solutions so that you can check your work.
 problem 6.3. This problem illustrates how the partition function Z is a dynamic thing that depends on the temperature.
 problem 6.5
 problem 6.7. In this problem, referring to Figure 6.2, you should see that the energy levels are given by the standard Bohr approximation, E_{n}=()13.6eV/n^{2}. Note the degeneracies here are given by g_{n}=2n^{2}. Thus g_{1}=2*1^{2}=2, g_{2}=2*2^{2}=8 and g_{3}=2*3^{2}=18 for n=1 (ground state), n=2 (first excited) and n=3 (second excited) states, respectively. Just as I discussed in class.
 Consider the hydrogenlike atom carbonV in stellar atmospheres. CarbonV is simply a carbon atom with 5 of its electrons ripped off by the extreme heat, and one electron remaining to jump around the usual energy levels. Calculate the temperature at which you would expect a ratio of 1/7 for a carbonV atom being in its n=8 state to being in its n=7 state. Remember to take degeneracy into account.
 problem 6.12. Note: If this problem doesn't make an impression on you about the universe, and how we can use what you are learning to discern something amazing about the universe, then you just don't have a pulse.
That's all for homework #9.
