Difference between the two following formulas

AI Thread Summary
The discussion clarifies the difference between two formulations of the first law of thermodynamics: dQ = dU + dW and dU = dQ + dW. In the first equation, dW refers to the work done by the system on its surroundings, while in the second, it indicates the work done by the surroundings on the system. The choice of convention varies among authors and disciplines, with physicists and chemists sometimes using different interpretations. Understanding these distinctions is crucial for applying the first law correctly in various contexts. Both formulas ultimately describe the same fundamental principles of energy conservation.
Kibz665
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Can some one please tell me what is the difference between the two following formulas and when it is used:
dQ=dU+dW
dU=dQ+dW
 
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Are you asking about the different conventions used by physicists and chemists for the 1st law..?
 
Kibz665 said:
Can some one please tell me what is the difference between the two following formulas and when it is used:
dQ=dU+dW
dU=dQ+dW
In the first equation, dW represents the work done by the system on the surroundings. In the second equation, dW represents the work done by the surroundings on the system. Both conventions are used, depending on the author.
 
Thanks that was very helpful.
 
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