Hello!
Could someone explain what w= -P∆V is used for?
w= -P∆V Purpose
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Re: w= -P∆V Purpose
The equation is used to calculate how much energy is given off into the surrounding from the system through work.
Dr. Lavelle explains that the equation itself is w = P∆V, however this is to calculate how much work the system produces. In order to calculate how much is lost to the surroundings, you would subtract this value from the system, hence the negative sign.
Hope this helps!
Dr. Lavelle explains that the equation itself is w = P∆V, however this is to calculate how much work the system produces. In order to calculate how much is lost to the surroundings, you would subtract this value from the system, hence the negative sign.
Hope this helps!
Last edited by Sammy Liu on Wed Jan 26, 2022 1:35 pm, edited 1 time in total.
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Re: w= -P∆V Purpose
This equation is used for calculating the work done for an irreversible expansion process. To use the same example as was used in lecture, if we have a gas inside a piston starting at 1 atm and the outside pressure is 0.5 atm, when we allow the piston to move it will expand abruptly. This is the system (the gas) doing work on the surroundings (pushing outside air out of the way). This equation will tell us how much work was lost by the system and gained by the surroundings.
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Re: w= -P∆V Purpose
It's used to determine the work that a system has performed based on its pressure and change in volume.
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Re: w= -P∆V Purpose
W=-PΔV is an equation used to find the work done by or on gas under isobaric conditions. This equation can be used in the first law of thermodynamics under these circumstances where ΔE=q-PΔV, highlighting the change in total energy of a system. Hope this helps some!
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