The expression for w in the first law of thermodynamics if negative implies all of the following EXCEPT:
Correct answer: C. Work done by the system
- A. Total internal energy has decreased
- B. The system has lost heat
- C. Work done by the system
- D. Work done on the system
Explanation
In the first law of thermodynamics, the expression for the change in internal energy of a system can be given as:∆U = Q - WIf the expression for work is negative, it means work is being done by the system rather than on the system. Therefore, the correct option is work done by the system.
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About First Law of Thermodynamics
The first law relates heat supplied, work done and the change in internal energy through energy conservation. Problems use sign conventions and apply the law to isothermal, adiabatic, isobaric and isochoric processes. Internal energy is a state function, while heat and work depend on the path followed.
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