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Homework Help: Specific volume of substances

  1. Mar 27, 2010 #1
    1. The problem statement, all variables and given/known data

    Must the specific volume of a substance change when it undergoes a change in pressure? Is this true for all substances?

    3. The attempt at a solution

    obviously this is true in most cases but my question is: are incompressible liquids an exception? When a liquid is attempted to be compressed, does the pressure change? Because if this is the case, then incompressible substances can undergo a change in pressure without the specific volume changing.
     
    Last edited: Mar 27, 2010
  2. jcsd
  3. Mar 27, 2010 #2

    Mapes

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    Yes. So-called "incompressible fluids" are idealizations, materials that undergo shear much more easily than they undergo compression.
     
  4. Mar 27, 2010 #3
    But when an incompressible substance undergoes a shear of 3000Kpa for example would the pressure of the substance be no different if it was to reach 3000Kpa through a rise in temperature rather than a change in shear?
     
  5. Mar 28, 2010 #4

    Mapes

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    I'm not really following you here. Shear stress doesn't cause hydrostatic pressure.
     
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