PHYS 330 Homework
 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)   Pre-Health information   R.U.F.R.E.E.Z.I.N.G.    pics from the north pole trip    the picture from the trip   Simple 2-liter 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 near-surface phase (calcite or aragonite) gives ways to the deeper-earth phase. Use the typical density of Earth as ≈4,000kg/m3. (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 one-variable equation. Then find the depth at which the near-surface phase (calcite or aragonite) gives ways to the deep-earth 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.