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  2. Density of air - Wikipedia

    en.wikipedia.org/wiki/Density_of_air

    At 20 °C and 101.325 kPa, dry air has a density of 1.2041 kg/m 3. At 70 °F and 14.696 psi, dry air has a density of 0.074887 lb/ft 3. The following table illustrates the air density–temperature relationship at 1 atm or 101.325 kPa: [citation needed]

  3. Thermal conduction - Wikipedia

    en.wikipedia.org/wiki/Thermal_conduction

    The differential form of Fourier's law of thermal conduction shows that the local heat flux density is equal to the product of thermal conductivity and the negative local temperature gradient . The heat flux density is the amount of energy that flows through a unit area per unit time.

  4. Air mass - Wikipedia

    en.wikipedia.org/wiki/Air_mass

    Continental and superior air masses are dry, while maritime and monsoon air masses are moist. Weather fronts separate air masses with different density (temperature or moisture) characteristics. Once an air mass moves away from its source region, underlying vegetation and water bodies can quickly modify its character. Classification schemes ...

  5. List of thermal conductivities - Wikipedia

    en.wikipedia.org/wiki/List_of_thermal_conductivities

    Tempered at 150°C and air cooled 32.2 32.2 32.8 Tempered at 200°C and air cooled 33.1 33.9 33.5 Tempered at 250°C and air cooled 36.8 36.4 37.2 Tempered at 300°C and air cooled 37.7 38.5 38.1 Tempered at 350°C and air cooled 38.1 38.5 38.9 List: Hattori, D., J. Iron Steel Inst. (London) 129 (1), 189–306, 1934 in TPRC I pp 1115–1120 ...

  6. Transport phenomena - Wikipedia

    en.wikipedia.org/wiki/Transport_phenomena

    There are some notable similarities in equations for momentum, energy, and mass transfer [7] which can all be transported by diffusion, as illustrated by the following examples: Mass: the spreading and dissipation of odors in air is an example of mass diffusion. Energy: the conduction of heat in a solid material is an example of heat diffusion.

  7. Thermal conductivity and resistivity - Wikipedia

    en.wikipedia.org/wiki/Thermal_conductivity_and...

    The thermal conductivity of a material is a measure of its ability to conduct heat.It is commonly denoted by , , or and is measured in W·m −1 ·K −1.. Heat transfer occurs at a lower rate in materials of low thermal conductivity than in materials of high thermal conductivity.

  8. Rayleigh number - Wikipedia

    en.wikipedia.org/wiki/Rayleigh_number

    The Rayleigh number describes the behaviour of fluids (such as water or air) when the mass density of the fluid is non-uniform. The mass density differences are usually caused by temperature differences. Typically a fluid expands and becomes less dense as it is heated. Gravity causes denser parts of the fluid to sink, which is called convection.

  9. Charge carrier density - Wikipedia

    en.wikipedia.org/wiki/Charge_carrier_density

    The carrier density is important for semiconductors, where it is an important quantity for the process of chemical doping.Using band theory, the electron density, is number of electrons per unit volume in the conduction band.