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 #7: Due Friday, October 10, by 5:30pm.
 problem 3.10. Don't forget to answer all the questions in part (d). And yes, I know that this is going backwards just a bit. But since we're using entropy in the Gibbs free energy differential dG=SdT+VdP, and entropy is such a slippery beast, this review will help.
 problem 5.28
 Let's extend problem 5.28.
(a) Still assuming contant T, find the depth below Earth's surface at which the nearsurface phase (calcite or aragonite) gives ways to the deeperearth phase. Use the typical density of Earth as ≈4,000kg/m^{3}.
(b) Now, let Earth's thermal gradient be ()20K/km (recall that this will mean that the temperature goes up as the depth goes downward). I want you to start from dG=()SdT+VdP, and then make this into a onevariable equation. Then find the depth at which the nearsurface phase (calcite or aragonite) gives ways to the deepearth phase. You must show enough of your numbers here so that I know that you actually calculated this by hand, instead of just having the numerical answer suddenly appear.
That's all for homework #7.
