Total Pressure

In physics, the term total pressure may indicate two different quantities, both having the dimensions of a pressure:

  • In fluid dynamics, total pressure refers to the sum of static pressure p, dynamic pressure q, and gravitational head, as expressed by Bernoulli's principle:
where ρ is the density of the fluid, g is the local acceleration due to gravity, and z is the height above a datum.
If the variation in height above the datum is zero, or so small it can be ignored, the above equation reduces to the following simplified form:
  • In a mixture of ideal gases, total pressure refers to the sum of each gas' partial pressure.

Famous quotes containing the words total and/or pressure:

    Parenting is the one area of my life where I can feel incompetent, out of control and like a total failure all of the time.
    —Attorney Father. As quoted in Reviving Ophelia, by Mary Pipher, ch. 4 (1994)

    Destiny is an absolutely definite and inexorable ruler. Physical ability and moral determination count for nothing. It is impossible to perform the simplest act when the gods say “no.” I have no idea how they bring pressure to bear on such occasions; I only know that it is irresistible.
    Aleister Crowley (1875–1947)