Thermodynamics: Adiabatic Process and Changes in Volume and Pressure

[joe215]

Homework Statement

If volume increases, but pressure decreases, is head added or removed (to a system)?

Homework Equations

I think that process would be adiabatic, in which case change in heat would be 0, but I am not sure.

 

[LowlyPion]

I think it's indeterminate without more information.

If the product of P*V remains the same with the increase of one and the decrease of the other then, all other things being equal, you could say it was adiabatic.

 

[Andrew Mason]

I think it's indeterminate without more information.

If the product of P*V remains the same with the increase of one and the decrease of the other then, all other things being equal, you could say it was adiabatic.

PV can remain constant (for an ideal gas) only if T is constant. But if V changes, then work is done on or by the gas, so its internal energy, hence temperature, cannot be constant without some flow of heat.

Since V increases, work is done by the gas. What does that tell you about heat flow?

AM