U=q or U=q+w?

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U=q or U=q+w?

Postby JennyCKim1J » Sun Jan 14, 2018 6:03 pm

When is the change in internal energy (U) equal to heat (q) and when is it equal to heat+work (q+w)? What is the difference between U=q and U=q+w?

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Re: U=q or U=q+w?

Postby PranithaPrasad » Sun Jan 14, 2018 6:36 pm

so U is always U=q+w, so as I understand it, U=q when there is no work being done by or on the system.

Jonathan Tangonan 1E
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Re: U=q or U=q+w?

Postby Jonathan Tangonan 1E » Sun Jan 14, 2018 7:41 pm

Yes this is true, the change in U= q + w. The change in internal energy is equal to the heat in the case that there are no other processes taking place except that of transferring energy as heat.

Nora 1F
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Re: U=q or U=q+w?

Postby Nora 1F » Sun Jan 14, 2018 11:51 pm

If you're looking for an example of this, problem 8.53 is a good start.

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