How do you find internal energy of U=Q+W?

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SUMMARY

The internal energy (U) of a system can be determined using the equation U = Q + W, where W represents work done on or by the system. In this discussion, specific work values are provided: Wac = 21000 J, Wbc = 0, and Wab = 91000 J. For thermally isolated systems or rapid processes, heat (Q) is considered zero, simplifying the calculation of internal energy. Conversely, for slow processes at a known temperature, internal energy can be calculated based on temperature and the type of gas involved.

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i figured out that
Wac=21000J
Wbc=0
Wab=91000J

how do you find internal energy of U=Q+W?
 

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It is the CHANGE of Internal Energy that is a process quantity,
related to other process quantities like Work and Heat.
If this is a "thermally isolated system" or the steps happen "quickly",
then you treat Q = 0 . If it happens "slowly" or at known Temperature,
then you know T and should calculate I.E. from T (depending on the kind of gas)
 

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