Some examples in text book make me confused when these two works are discussed at the same time.(adsbygoogle = window.adsbygoogle || []).push({});

One of the works is the (mechanical) work in work-energy theorem:

[tex]

\Delta K = \sum_iW_i,

[/tex]

where [tex]K[/tex] is the kinetic energy and [tex]W_i[/tex] was the work done by the [tex]i[/tex]-th force.

The other is the (thermodynamical) work in the first law of thermodynamics:

[tex]

\Delta U = Q + W,

[/tex]

where [tex]U[/tex] is the internal energy of the system, [tex]Q[/tex] is the heat transfered, and [tex]W[/tex] is the work done on the system by surroundings.

Are the two works the same when we want to use work-energy theorem and the first law of thermodynamics at the same time?

Can any one give some criterion to distinguish these two works ?

Thank you .

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# What is the difference between these two works ?

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