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### calculating q and w in isochoric systems

Posted: Mon Feb 12, 2018 1:58 pm
What equations do we use to find q and w when there is a change in pressure in an isochoric system (a system where the volume doesn't change)? An example of them asking for this is #4 on the practice midterm.

### Re: calculating q and w in isochoric systems

Posted: Mon Feb 12, 2018 2:19 pm
In an isochoric system, w = 0.

You'd need know about a temperature change to calculate $\Delta U$, and from that you can calculate q.

### Re: calculating q and w in isochoric systems

Posted: Mon Feb 12, 2018 2:21 pm
If there is no change in volume then no work is done according to the equation for work w=-P$\Delta$V. Since $\Delta$U = q+w, and work is 0 then q is equal to $\Delta$U. And q is generally equal to mC$\Delta$T.

### Re: calculating q and w in isochoric systems

Posted: Mon Feb 12, 2018 2:27 pm
Ok that makes sense. Thank you!