## Thermodynamics for W

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

Guillermo Vega 1H
Posts: 10
Joined: Wed Nov 18, 2015 3:00 am

### Thermodynamics for W

I don't really understand when we should compute with the formula w=-nRTln(V2/V1). Is this for only isothermal expansions or are there other situations in which we can use the formula?

ntruong2H
Posts: 50
Joined: Sat Jul 09, 2016 3:00 am
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### Re: Thermodynamics for W

Guillermo Vega 1H wrote:I don't really understand when we should compute with the formula w=-nRTln(V2/V1). Is this for only isothermal expansions or are there other situations in which we can use the formula?

Use this formula when pressure is not constant.

Manasvi Paudel 1A
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Joined: Sat Jul 22, 2017 3:00 am

### Re: Thermodynamics for W

You use that equation when pressure is not constant. -PdeltaV is used when pressure is constant.

Ozhen Atoyan 1F
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Joined: Thu Jul 27, 2017 3:01 am
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### Re: Thermodynamics for W

To add onto the previous post, I believe you utilize this equation only when you have an isothermal reversible expansion.