Thermodynamics Need help for AP test in 40 minutes

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In an isothermal expansion of a gas, the pressure decreases while the volume increases. The work done by the gas during this transition can be calculated using the integral of pressure with respect to volume, represented as ∫PdV. This integral yields a positive value when the volume change (dV) is positive, indicating work done by the gas. Conversely, the work done on the gas would be negative in this scenario. Understanding these concepts is crucial for success in thermodynamics, especially for AP test preparation.
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Thermodynamics! Need help for AP test in 40 minutes!

Lets say that you have a gas that starts at an initial pressure P, volume V, and temperate T.

Then it undergoes an isothermal expansion, during with pressure decreases and volume increases.

What is the work done BY the gas during the transition?
What is the work done ON the gas during the transition?

Now, if I want to do this with integrals (i.e. area under the curve), for work done BY the gas, would it be the POSITIVE AREA under the curve?
 
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ƒ(x) said:
Lets say that you have a gas that starts at an initial pressure P, volume V, and temperate T.

Then it undergoes an isothermal expansion, during with pressure decreases and volume increases.

What is the work done BY the gas during the transition?
What is the work done ON the gas during the transition?

Now, if I want to do this with integrals (i.e. area under the curve), for work done BY the gas, would it be the POSITIVE AREA under the curve?
Yes. Work done by the gas is \int Pdv. If dv is positive, the integral (area under PV graph) is positive.

AM
 
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