What is Temperature: Definition and 1000 Discussions

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. B

    Investigating the Impact of Heating a Substance on Room Temperature

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  2. B

    Speed of sound related to absolute temperature

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  3. Low-Q

    Calculating energy requirements to sustain temperature

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  4. Hiero

    What is the true meaning of temperature? Is it global or local?

    Temperature is often imagined as a scalar field varying over (physical) space. Yet temperature seems to be generally defined as the (reciprocal) rate of change (with fixed V,N) of the entropy of a system w.r.t. the energy of that system; a seemingly global property. Is this definition only for...
  5. tanaygupta2000

    Statistical Mechanics: Two systems reaching an equilibrium temperature

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  6. WateryFungi

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  7. Graeme M

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  8. H

    What's the normal low-load working temperature for an SMPS transformer?

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  9. sneakycooky

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  10. Harini Krishna

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  11. C

    Temperature variations in body regions

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  12. J

    Heat transfer through a MultiLayer Cylinder (find the Temperature inside)

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  13. patric44

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  14. G

    Below what freezing temperature is it not possible to have frost?

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  15. V

    Temperature of the tank in a superheater

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  16. ib43

    Thermal physics problem -- Pressure and temperature of air in a refrigerator

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  17. B

    Temperature inside an enclosed space

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  18. Z

    Threshold voltage shift vs temperature

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  19. Y

    Temperature change in a gas expansion

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  20. M

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  21. Y

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  22. M

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  23. NP04

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  24. Rahulx084

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  25. W

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  26. B

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  27. Sabra_a

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    I Mobility and resistivity as a function of temperature

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  31. C

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  32. S

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  33. karush

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  34. M

    High temperature (~950 C) heating blanket

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  35. T

    What is the Correct Way to Plot a 2D Ising Model Temperature Chart?

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  36. K

    "Heat resistance temperature" and melting point?

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  37. Diracobama2181

    Heat Capacity of a Fermi Gas at Low Temperature

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  38. pangru

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  39. T

    Repost/Merged Threads - Density: pressure and temperature dependency

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  40. P

    Temperature and non-equilbrium thermodynamics

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  41. Frigus

    Do two boxes expand equally with temperature if one has a Hole?

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  42. Frigus

    Temperature: Definition & Atomic Level Effects

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  43. C

    Temperature needed to destory bacterial spores

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  44. men5j2s

    Estimate the temperature change due to vaporizing liquid

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  45. Anand Sivaram

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  46. Frigus

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  47. Sai Maurice

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  48. P

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  49. Rifat amin

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    Not attempt
  50. E

    Temperature dependence of ΔS°, ΔG° and ΔH°

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