What is Adiabatic expansion: Definition and 95 Discussions

In thermodynamics, an adiabatic process (from the Greek adiábatos, meaning “impassable”) is a type of thermodynamic process which occurs without transferring heat or mass between the system and its surroundings. Unlike an isothermal process, an adiabatic process transfers energy to the surroundings only as work. It also conceptually supports the theory used to explain the first law of thermodynamics and is therefore a key thermodynamic concept.
Some chemical and physical processes occur too rapidly for energy to enter or leave the system as heat, allowing a convenient "adiabatic approximation". For example, the adiabatic flame temperature uses this approximation to calculate the upper limit of flame temperature by assuming combustion loses no heat to its surroundings.
In meteorology and oceanography, adiabatic cooling produces condensation of moisture or salinity, oversaturating the parcel. Therefore, the excess must be removed. There, the process becomes a pseudo-adiabatic process whereby the liquid water or salt that condenses is assumed to be removed upon formation by idealized instantaneous precipitation. The pseudoadiabatic process is only defined for expansion because a compressed parcel becomes warmer and remains undersaturated.

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  1. A

    Thermodynamics question (Adiabatic expansion)

    Hello, I am taking a course on thermodynamics and there was a question on our textbook( "Thermodynamics of Materials" by David V. Ragone) and I can't understand the solution given to me by my prof and I think it is wrong. Homework Statement An evacuated (P=0), insulated tank is surrounded...
  2. B

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  3. C

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  4. K

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  5. N

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  6. B

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  7. Rapier

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  8. O

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  10. L

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  11. R

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  12. O

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  13. Q

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  14. Q

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  15. W

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  16. C

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  17. A

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  18. P

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  19. R

    Adiabatic expansion of an ideal gas.

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  20. W

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  21. C

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  22. T

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  23. W

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  24. K

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  29. O

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  31. N

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  32. P

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  33. S

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  34. F

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  35. J

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  36. G

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  37. nicksauce

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  38. M

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  39. A

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  40. P

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  41. E

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  42. E

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  43. E

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  44. S

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  45. T

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