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A question asked: If we decrease the velocity by 2 of a gas in a closed container what happens to the Temperature?
A: In the explanation the book explained that we cannot use PV=nRT bc we cannot assume Pressure is constant. Instead we have to use U=q+w, and we cancel q --> change in U=w --> change in U=3/2nRT.
So Temperature goes up because work is being done on the system.
logically it makes sense. Work is done=internal energy goes up=temp goes up.
But why can we use the equation U=w When Work=P x change in V -->we also must assume pressure is not changing?!!?
A: In the explanation the book explained that we cannot use PV=nRT bc we cannot assume Pressure is constant. Instead we have to use U=q+w, and we cancel q --> change in U=w --> change in U=3/2nRT.
So Temperature goes up because work is being done on the system.
logically it makes sense. Work is done=internal energy goes up=temp goes up.
But why can we use the equation U=w When Work=P x change in V -->we also must assume pressure is not changing?!!?