The work in a system is given by(adsbygoogle = window.adsbygoogle || []).push({});

[tex]F\cdot\Delta h[/tex]

[tex]P\cdot A\cdot\Delta h[/tex]

[tex]P\cdot \Delta V[/tex]

when one calculate work one always uses pressure from surroundings. Why is it so. I get that work becomes linear then because p is constant but I thought that if one use newtons third law that a system is standing still if forces are equal then work as a physical change would be done if p is larger in either system or surroundings. But if one look at force from system when p is larger in system why cant one use that to calculate work on surroundings?

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# System of pressure

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