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Homework Help: Quick thermodynamics question

  1. Dec 1, 2008 #1
    1. The problem statement, all variables and given/known data

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

    2. Relevant equations


    I think that process would be adiabatic, in which case change in heat would be 0, but im not sure.
     
  2. jcsd
  3. Dec 1, 2008 #2

    LowlyPion

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    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.
     
  4. Dec 2, 2008 #3

    Andrew Mason

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    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
     
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