Classical thermodynamics problem

AI Thread Summary
The Second Law of Thermodynamics can be expressed through Kelvin's statement, which asserts that no process can solely convert heat into work, or Clausius' statement, which states that heat cannot spontaneously flow from a colder body to a hotter one. The discussion also addresses a problem involving the heat capacity per unit volume of a solid at low temperatures, given as CT3. An attempt to derive the internal energy resulted in the incorrect expression of internal energy as CT4. The participant seeks assistance to solve the problem efficiently, emphasizing the urgency due to upcoming comprehensive exams.
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Homework Statement



(i) State the Second Law of Thermodynamics in one or other of its forms.

(ii) The heat capacity per unit volume of a particular solid at low temperatures is equal to CT3; find expressions for its internal energy and entropy S per unit volume (ignoring the effects of thermal expansion).

Homework Equations



The Attempt at a Solution



(i) Kelvin's statement: No process is possible whose sole effect is complete conversion of heat into work.

Clausius' statement: No process is possible whose sole effect is to transfer heat from a colder to a hotter body.

(ii) Not sure. Any help would be awesome.
 
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Atleast show us the attempt
 
Heat capacity = Internal energy/ Temperature, so Internal energy = CT4. Now, I know that this is wrong, but that's the point of me coming to the forum, so I can get the problem done quickly. Otherwise I can just read the lecture notes and get the problem done in 60 long and boring minutes, which isn't fun becasue I am a third year student and I am studying this for the comprehensive paper and if I take this long to do one problem, then i will take eternity to finish all the first and second year courses and so I might as well pack my bag and run for home.
 
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