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  2. Chvorinov's rule - Wikipedia

    en.wikipedia.org/wiki/Chvorinov's_rule

    Chvorinov's rule is a physical relationship that relates the solidification time for a simple casting to the volume and surface area of the casting. It was first expressed by Czech engineer Nicolas Chvorinov in 1940. [1] [2]

  3. Penman–Monteith equation - Wikipedia

    en.wikipedia.org/wiki/Penman–Monteith_equation

    The Penman–Monteith equation approximates net evapotranspiration (ET) from meteorological data, as a replacement for direct measurement of evapotranspiration. The equation is widely used, and was derived by the United Nations Food and Agriculture Organization for modeling reference evapotranspiration ET 0 .

  4. Dead time - Wikipedia

    en.wikipedia.org/wiki/Dead_time

    Dead time. For detection systems that record discrete events, such as particle and nuclear detectors, the dead time is the time after each event during which the system is not able to record another event. [1] An everyday life example of this is what happens when someone takes a photo using a flash - another picture cannot be taken immediately ...

  5. Sunrise equation - Wikipedia

    en.wikipedia.org/wiki/Sunrise_equation

    Sunrise equation. A contour plot of the hours of daylight as a function of latitude and day of the year, using the most accurate models described in this article. It can be seen that the area of constant day and constant night reach up to the polar circles (here labeled "Anta. c." and "Arct. c."), which is a consequence of the earth's inclination.

  6. Klinkenberg correction - Wikipedia

    en.wikipedia.org/wiki/Klinkenberg_correction

    Klinkenberg correction. In Petrophysics a Klinkenberg correction is a procedure for calibration of permeability data obtained from a minipermeameter device. A more accurate correction factor can be obtained using Knudsen correction. When using nitrogen gas for core plug measurements, the Klinkenberg correction is usually necessary due to the so ...

  7. Friis transmission equation - Wikipedia

    en.wikipedia.org/wiki/Friis_transmission_equation

    Spurious emission. Techniques. v. t. e. The Friis transmission formula is used in telecommunications engineering, equating the power at the terminals of a receive antenna as the product of power density of the incident wave and the effective aperture of the receiving antenna under idealized conditions given another antenna some distance away ...

  8. Eötvös effect - Wikipedia

    en.wikipedia.org/wiki/Eötvös_effect

    The force of gravity and the normal force. The resultant force acts as the required centripetal force. The mathematical derivation for the Eötvös effect for motion along the Equator explains the factor 2 in the first term of the Eötvös correction formula. What remains to be explained is the cosine factor.

  9. Tsiolkovsky rocket equation - Wikipedia

    en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation

    A rocket's required mass ratio as a function of effective exhaust velocity ratio. The classical rocket equation, or ideal rocket equation is a mathematical equation that describes the motion of vehicles that follow the basic principle of a rocket: a device that can apply acceleration to itself using thrust by expelling part of its mass with high velocity can thereby move due to the ...