Recent content by Chestermiller

  1. Chestermiller

    B Static pressure inside the glass of water

    It doesn’t.
  2. Chestermiller

    B Static pressure inside the glass of water

    Volume per unit mass, For an incompressible fluid,fhe equation of state is degenerate.
  3. Chestermiller

    B Static pressure inside the glass of water

    Yes, but for a compressible fluid, the equation of state says that the pressure is independent of specific volume.
  4. Chestermiller

    B Static pressure inside the glass of water

    All the equations you have written are the incompressible case.
  5. Chestermiller

    B Static pressure inside the glass of water

    If you are considering the liquid water as incompressible. then its specific volume is independent of pressure, and the static pressure (as you call it) is equal to the hydrostatic pressure at all depths. The equation of state for an ideal gas is $$P=\frac{\rho RT}{M}$$where M is the molecular...
  6. Chestermiller

    B Static pressure inside the glass of water

    Your equation for the hydrostatic pressure is incorrect if you are allowing the water to have a pressure which varies with specific volume (i.e,. your 'static pressure relationship). That is, if the water is considered compressible.
  7. Chestermiller

    B Static pressure inside the glass of water

    If I understand you correctly, the hydrostatic pressure must match the static pressure at all depths in the glass.
  8. Chestermiller

    B Static pressure inside the glass of water

    The equation of state of liquid water is approximated by $$\rho=\rho_0e^{(-\alpha(T-T_0)+\frac{P-P_0}{B})}$$where ##\alpha## is the coefficient of thermal expansion and B is the bulk modulus; ##T_0=293 K## and ##P_0=1 atm##. So the hydrostatic equation reads $$\frac{dP}{dh}=\rho...
  9. Chestermiller

    B Static pressure inside the glass of water

    What is the difference between static pressure and hydrostatic pressure in this system? What is your definition of these terms?
  10. Chestermiller

    Thermodynamic Work vs Mechanical Work

    Work is work. It is the integral of the applied force over a displacement. In thermodynamics, you have to very carefully define what you are calling your system, and where your system ends and its surrounding begins. This choice is entirely up to you. You also have to specify what is...
  11. Chestermiller

    B How to characterize a rubber ball moving horizontally and bouncing off of a vertical wall?

    To simplify things, replace the ball with a short elastic rod and neglect gravity. The key to understanding what happens in impact of the rod against the wall is to recognize that the rod is not a rigid body and so it does not have to stop all at once. Different parts of the rod deform at...
  12. Chestermiller

    Thermodynamics: Cooling of a heated block of iron in contact with air

    The hard part of attacking physical is to articulate in words the physical mechanisms involved and translate these into a set of equations. Solving the equation(s) is supposed to be a gimme.
  13. Chestermiller

    Thermodynamics: Cooling of a heated block of iron in contact with air

    Are you saying that you don't know how to solve this linear first order ordinary differential equation and that you want. us to solve it for you?
  14. Chestermiller

    Thermodynamics: Cooling of a heated block of iron in contact with air

    It goes like this: $$MC_p\frac{dT}{dt}=-kS(T-20)$$The initial temperature is 1500 C and, apparently, your final temperature is supposed to be 40C.
  15. Chestermiller

    Engineering Hydroprocessing Unit material and energy Balance

    In thess equations, the 0.9724 should be 0.8
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