Consider a systen of N non-interacting particles for which the energy of each pa
ID: 2255343 • Letter: C
Question
Consider a systen of N non-interacting particles for which the energy of each particle can assume two and only two distinct values: 0 and E (E>0). denote N1 and N2 to be the occulation numbers of the levels 0 and E respectively. The fixed ttoal energy of the system is U.
a) Find the entropy of the system.
b) Find the temperature as a function of U. For what range of values is N1 is T<0?
c) In which direction does heat flow when a system of negative temerature is brought into thermal contact with a system of positive temperature? Why?
Explanation / Answer
entropy = N1 +N2 +N3 ..+Nn
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temperature =entropy/E
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when system of negative temperature is brought in contact with positive temperature heat flows from positive to negative temperature . as heat always flow from high to low temperature
negative temperature only implies that it is below some fixed temperature