Temperature Definition and 1000 Threads

Temperature is a physical quantity that expresses hot and cold. It is the manifestation of thermal energy, present in all matter, which is the source of the occurrence of heat, a flow of energy, when a body is in contact with another that is colder or hotter.
Temperature is measured with a thermometer. Thermometers are calibrated in various temperature scales that historically have used various reference points and thermometric substances for definition. The most common scales are the Celsius scale (formerly called centigrade, denoted as °C), the Fahrenheit scale (denoted as °F), and the Kelvin scale (denoted as K), the last of which is predominantly used for scientific purposes by conventions of the International System of Units (SI).
The lowest theoretical temperature is absolute zero, at which no more thermal energy can be extracted from a body. Experimentally, it can only be approached very closely (100 pK), but not reached, which is recognized in the third law of thermodynamics.
Temperature is important in all fields of natural science, including physics, chemistry, Earth science, astronomy, medicine, biology, ecology, material science, metallurgy, mechanical engineering and geography as well as most aspects of daily life.

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  1. D

    How can i measure the plasma temperature

    Hi there i wonder how can i measure the plasma temperature ? and what is magnetic field have the impact to plasma or not? Thank you all.
  2. W

    Find the equilbrium temperature

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  3. C

    How Does Temperature Relate to Thermal Energy and Kinetic Energy?

    Is the following correct? Temperature is the measure of how hot or cold something is; not how much thermal energy it has. Examples; 1 kg of boiling water has a temperature of 100 degrees C and has heat energy of 4.184 kJ (the specific heat capacity of water). 1 kg of lead heated to a...
  4. P

    How to maintain commercial scale CSTR temperature?

    I'm currently doing a design for my final year studies and it's regarding esterification process. My proposed reactor is CSTR, operating at a temperature of 60C and 400 kPa. Reactants are methanol and jatropha oil with sulphuric acid catalyst. For a commercial scale production of biodiesel...
  5. C

    Thermodynamics of mercury thermometers

    The space above the mercury column in a thermometer ordinarily is evacuated, but due to faulty manufacture, a particular thermometer has a pressure of 2 mmHg of air in this space when the whole thermometer is immersed in a bath at 0 degrees Celsius. Calculate the pressure of the air when the...
  6. Borek

    Melting Nickel Ball: Temperature & Radius Effects

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  7. Andre

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  8. Nantes

    If the air temperature were the same as the human body's....

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  9. P

    Air flow from large to small tube.What happens to pressure?

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  10. Rodwen

    Light absorbtion and change in temperature of liquids

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  11. P

    Thermodynamics -- Calculate the pressure and temperature

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  12. kester

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  13. A

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  14. Stephanus

    Earth Core Temperature: Causes & Impact

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  15. D

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  16. A

    Interpreting Kinetic Temperature for Solids / Liquids

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  17. B

    How room temperature will change in 1 hour

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  18. A

    Axial Deformation due to Temperature Change and Load

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  19. R

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  20. C

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  21. Y

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  22. Jimster41

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  23. PytrTchaikovsky

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  24. FarabiBinImran

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  25. D

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  26. K

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  27. S

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  29. P

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  30. skepticwulf

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  31. G

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  32. PytrTchaikovsky

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  33. A

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  34. TESL@

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  35. Q

    Does weight / inertia / momentum change with temperature?

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  36. E

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  37. marcophys

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  38. A

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  39. F

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  40. HelloCthulhu

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  41. T

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  42. S

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  43. EternusVia

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  44. D

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  45. A

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  46. K

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  47. Z

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  48. Z

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  49. M

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  50. Hyo X

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