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Homework Help: Thermal Equilibrium of Blocks In Contact - please help

  1. Dec 4, 2009 #1
    1. The problem statement, all variables and given/known data
    A nano particle consisting of four iron atoms (object 1) initially has 1 quantum of energy. It is brought into contact with another nano particle, consisting of two iron atoms (object 2), which has 2 quanta of energy. The mass of one mole of iron is 56 gram.

    a. Using the Einstein model of a solid, calculate and plot ln(W1) versus q1 (the number of quanta of object 1), ln(W2) versus q1, and ln(Wtotal) versus q1 (put all three plots on the same graph). Show your work and explain how you obtained the results shown.
    b. Calculate the approximate temperature of the objects when they are in equilibrium. State clearly what assumptions or approximations you made.

    2. Relevant equations

    Number of micro states:
    Omega=(q + N-1)! / q!(N-1)!
    Definition of entropy S:
    S = k ln(Omega)
    Vibrational Energy Levels:
    Definition of temperature T:
    T= (c(change)q)/(change)s

    3. The attempt at a solution
    First I made a chart with q1, q2, W(omega)1, W2, S1 and S2.
    The question limits us to four quantum states (0,1,2,3) - those are the values of q1 respectivley. q2 would be (3,2,1,0) when dealing with the number of micro states equations q=q1 and N=q2 - though my numbers for omega one came out wrong with the q1's and q2's I assumed my W was (1,2,1,-1/3) - obviously it is impossible for the W to be decreasing Another thing to note that the ksubs in the vibrational energy equation is equal to the constant c needed in the temperature equation I thinkm as well as the entropy equation. I have hit a block and I am not sure how to get around this - either my q's are wrong or I am manipulating the equation incorrectly, or i have totally missed the concept.

    please, PLEASE help - the textbook is lacking of proper explanation and I could not find specifically to the best of my knowledge what I needed to online - I very much appreciate any help, thank-you.

    **in addition - please let me know if this problem is being worked on, if it is not and it is because I have not given enough information or there is some other form of error let me know and I will fix it promptly - thanks

    *** I do not need help with the actual graphing part, I am just having trouble filling out the table with the necessary information that in the end is needed to do the actual graphing.
    Last edited: Dec 4, 2009
  2. jcsd
  3. Dec 4, 2009 #2
    again, please let me know if I was not clear enough : )
  4. Dec 4, 2009 #3
    sorry to bump - but i really need the help, any thoughts or ideas at all?
  5. Dec 4, 2009 #4
    please let me know if there is any reason in paticular this question was not answered - i dont mean to sound pushy, I just want to know if there was something I did wrong.
  6. Dec 5, 2009 #5
    bumping is juvenile, i know...
  7. Dec 6, 2009 #6
    sigh bump
  8. Dec 6, 2009 #7
    oh god cant anyone out there help me- this is only a freshman class. I know your all smart and are apt enough in this field to at least give me some pointers- share the knowledge of physics please!!
  9. Dec 8, 2009 #8
    HELLPPPP - the test is in 4 hours, I really need to understand this, thank - you
  10. Dec 8, 2009 #9
    WHAT DO YOU PEOPLE HAVE AGAINST THIS PROBLEM?! ahh i give up on this, lost cause
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