- #1

- 6

- 0

In my physics textbook they discuss work done by ideal gas processes. The equation they give is W

_{gas}= pΔV. I'm trying to figure it out if this is work done ON the gas by the surroundings, or work done BY the gas on surroundings.

From a previous chapter, they presented the conservation of energy equation as E

_{i}+ W

_{net,ext}= E

_{f}. Work in this equation is the net, external work on the system, such that +W is work by the surroundings on the system, and -W is work by the system on the surroundings. It would seem from this preliminary chapter that we would be defining any W as work ON the system by surroundings.

However W

_{gas}can't possibly be work done ON the gas, because if a gas is expanding, it supposedly has +W

_{gas}even though it is doing work on the surroundings (therefore W

_{net,ext}should be negative). Could anybody confirm my thinking and does anybody know a good way to distinguish these two?