## Midterm Q5

$w=-P\Delta V$
and
$w=-\int_{V_{1}}^{V_{2}}PdV=-nRTln\frac{V_{2}}{V_{1}}$

Rachel Brown 3A
Posts: 52
Joined: Fri Sep 29, 2017 7:06 am

### Midterm Q5

On the solutions for the midterm, it says that after solving for work = -158, delta u = +158. Why is this the case? Even though work=delta u if q=0

Jonathan Tangonan 1E
Posts: 50
Joined: Sat Jul 22, 2017 3:01 am

### Re: Midterm Q5

It is +158J because it returns back to the original internal energy. Delta U in step 1 is -158J so in order to return to its original internal energy in step 2 it must be +158J.

Michael Downs 1L
Posts: 29
Joined: Thu Jul 13, 2017 3:00 am

work=-delta U