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Belle Calforda3f
Posts: 67
Joined: Fri Sep 29, 2017 7:07 am


Postby Belle Calforda3f » Fri Feb 09, 2018 11:01 pm

I am still so confused about work. How does volume affect it?

Harjas Sabharwal 1G
Posts: 42
Joined: Sat Jul 22, 2017 3:01 am

Re: work

Postby Harjas Sabharwal 1G » Fri Feb 09, 2018 11:06 pm

When the volume of the system changes then the system has to do or have work done upon the system.
For example if the system expands, it is doing work to more the surroundings out of the way. Hence, work is being done on the system.
If a system is compressed, the surroundings are making the system smaller and thus doing work on the system.

Lisa Tang 1C
Posts: 62
Joined: Fri Sep 29, 2017 7:05 am
Been upvoted: 2 times

Re: work

Postby Lisa Tang 1C » Fri Feb 09, 2018 11:14 pm

There are two types of work a system can do. There is nonexpansion work and expansion work. Expansion work is the work that concerns a change in the volume of a system. The equation relating work to volume is w=-PexV, but this only applies when external pressure is constant. When external pressure is not constant, we use w=-nRT*ln(Vfinal/Vinitial). This is how you figure out a change in volume's effect on work.

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