Pressure Definition and 999 Threads

Pressure (symbol: p or P) is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure (also spelled gage pressure) is the pressure relative to the ambient pressure.
Various units are used to express pressure. Some of these derive from a unit of force divided by a unit of area; the SI unit of pressure, the pascal (Pa), for example, is one newton per square metre (N/m2); similarly, the pound-force per square inch (psi) is the traditional unit of pressure in the imperial and U.S. customary systems. Pressure may also be expressed in terms of standard atmospheric pressure; the atmosphere (atm) is equal to this pressure, and the torr is defined as 1⁄760 of this. Manometric units such as the centimetre of water, millimetre of mercury, and inch of mercury are used to express pressures in terms of the height of column of a particular fluid in a manometer.

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  1. S

    B Angular momentum, degeneracy pressure, and cosmic inflation

    Considering the angular momentum of a collapsing star preventing it from resulting in a black hole by degeneracy pressure, are there ekpyrotic universe models that include angular momentum and degeneracy pressure as key factors of cosmic inflation?
  2. R

    I Energy density and pressure of perfect fluid

    is there any way to derive p=rho/3 from 4 vector or stress-energy tensor?
  3. Const@ntine

    Compute the Work: Pressure analogous to Volume

    Homework Statement One mole of an ideal gas is warmed slowly, so that the pressure and volume go from (Pi, Vi) to (3Pi, 3Vi), in such a way that the pressure is analogous to the volume. a) What's the Work (W)? b) What is the correlation between the temperature and the volume during that...
  4. PainterGuy

    Pressure exerted by an ideal gas

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  5. Const@ntine

    Finding the Remaining Pressure of a Gas After Removing 2/3rds

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  6. PainterGuy

    Why does atmospheric pressure increase as you go closer to the Earth's surface?

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  7. G

    Can we accurately measure water pressure using DIY water towers?

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  8. H

    Pressure Chamber with Flat Door

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  9. E

    Water Container Force: Impact of Finger Dip on Scale Measurement

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  10. A

    Stagnation pressure across a normal shock wave

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  11. U

    Pressure dependence of the equilibrium constant for an ideal gas

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  12. P

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  13. G

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  14. wolf1728

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  15. S

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  16. N

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  17. W

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  18. I

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  19. K

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  20. N

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  21. chopnhack

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  22. Baritone

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  23. T

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  24. Builder

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  25. TheRumpus

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  26. SlowThinker

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  27. single0speed

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  28. J

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  31. N

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  32. D

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  33. B

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  34. Pushoam

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  35. D

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  36. Edison Bias

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  37. X

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  38. M

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  39. A

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  40. S

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  41. D

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  42. G

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  43. E

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  44. Kevin Shen

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  45. J

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  46. J

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  47. T

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  48. T

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  49. H Psi equal E Psi

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  50. T

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