1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Einstein model of solids, energy in joules of one quantum

  1. Nov 20, 2008 #1
    1. The problem statement, all variables and given/known data
    the stiffness of the interatomic "spring" (chemical bond) between atoms in a block of lead is 5 N/m. Since in our model each atom is connected to two springs, each half the length of the interatomic bond, the effective "interatomic spring stiffness" for an oscillator is 4*5 N/m = 20 N/m. The mass of one mole of lead is 207 grams (0.207 kilograms).

    What is the energy, in joules, of one quantum of energy for an atomic oscillator in a block of lead?


    2. Relevant equations
    E= hbar*sqrt(k/m)


    3. The attempt at a solution
    E=(1.05457148e-34)(sqrt(20/.207)
    E=1.033e-33 J

    After this i thought that i would just divide this number by the total number of oscillators and get the energy for one quanta, but that doesnt work. This is the only equation given in the book besides the one for finding the possible number of microstates, but i dont see how that would help.
     
  2. jcsd
  3. Nov 21, 2008 #2

    Redbelly98

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    I think you're done. It asks for the quantum of energy for an (as in one) atomic oscillator, and that is what you did.
     
  4. Nov 21, 2008 #3
    Oh I figured out why it was wrong, its supposed to be the mass of one atom, not one mole. so m = .207/6.02e23
    E=hbar*sqrt(20/m)
    E=8.0427e-22 J
     
  5. Nov 21, 2008 #4

    Redbelly98

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    Aaargh, I missed that. Good catch.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Einstein model of solids, energy in joules of one quantum
  1. Energy - Joules (Replies: 1)

Loading...