What is Pressure: Definition and 1000 Discussions

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. M

    Fluid Mechanics problem: Oil pressure calculations in pipe flow

    Problem Statement: An oil with density 900 kg/m3 and viscosity 0.18 Ns/m2 flows through a circular pipe which inclines upwards at 40° to the horizontal. The length of the pipe is 10 m and the diameter is 6 cm. The fluid pressure at the lower end of the pipe is 350 kPa and the pressure at the...
  2. J

    I How Do You Calculate Initial Pressure and Final Volume in Adiabatic Expansion?

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  3. J

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  4. AttoBlaze

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  5. wasmaro

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  6. mateusz24052

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  8. Chandrakanth_balusa

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  9. L

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  10. W

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  11. F

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  12. Roy S Ramirez

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  13. pvorisek25

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  14. Andrea Vironda

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  15. newsunxu

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  16. J

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  17. G

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  18. theycallmevirgo

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  19. S

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  21. J

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  22. A

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  23. M

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  24. E

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  25. Scargo

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  28. D

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  31. J

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  32. L

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  33. Kako

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  34. M

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  35. avishay

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  36. T

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  37. M

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  38. R

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  39. Plat

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  40. C

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  41. C

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  42. E

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  43. patric44

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  44. R

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  45. Sanborn Chase

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  46. P

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  47. C

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  48. P

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  49. dlgoff

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  50. M

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