enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Mach number - Wikipedia

    en.wikipedia.org/wiki/Mach_number

    It is first determined whether M is indeed greater than 1.0 by calculating M from the subsonic equation. If M is greater than 1.0 at that point, then the value of M from the subsonic equation is used as the initial condition for fixed point iteration of the supersonic equation, which usually converges very rapidly. [ 8 ]

  3. Hydraulic jumps in rectangular channels - Wikipedia

    en.wikipedia.org/wiki/Hydraulic_Jumps_in...

    The height of the hydraulic jump, similar to length, is useful to know when designing waterway structures like settling basins or spillways. The height of the hydraulic jump is simply the difference in flow depths prior to and after the hydraulic jump. The height can be determined using the Froude number and upstream energy. Equations:

  4. Orders of magnitude (length) - Wikipedia

    en.wikipedia.org/wiki/Orders_of_magnitude_(length)

    5 mlength of an elephant; 5.2 mheight of a giraffe [123] 5.5 mheight of a Baluchitherium, the largest land mammal ever lived; 6.5 m – wingspan of Argentavis, the largest flying bird known; 6.7 mlength of a Microchaetus rappi; 7.4 m – wingspan of Pelagornis, the bird with longest wingspan ever. [124] 7.5 m – approximate ...

  5. Wind profile power law - Wikipedia

    en.wikipedia.org/wiki/Wind_profile_power_law

    The power law is often used in wind power assessments [4] [5] where wind speeds at the height of a turbine ( 50 metres) must be estimated from near surface wind observations (~10 metres), or where wind speed data at various heights must be adjusted to a standard height [6] prior to use.

  6. Roughness length - Wikipedia

    en.wikipedia.org/wiki/Roughness_length

    As an approximation, the roughness length is approximately one-tenth of the height of the surface roughness elements. For example, short grass of height 0.01 meters has a roughness length of approximately 0.001 meters. Surfaces are rougher if they have more protrusions. Forests have much larger roughness lengths than tundra, for example.

  7. Peak ground acceleration - Wikipedia

    en.wikipedia.org/wiki/Peak_ground_acceleration

    Peak ground acceleration can be expressed in fractions of g (the standard acceleration due to Earth's gravity, equivalent to g-force) as either a decimal or percentage; in m/s 2 (1 g = 9.81 m/s 2); [7] or in multiples of Gal, where 1 Gal is equal to 0.01 m/s 2 (1 g = 981 Gal).

  8. ISO metric screw thread - Wikipedia

    en.wikipedia.org/wiki/ISO_metric_screw_thread

    The length of a machine screw or bolt is indicated by an × and the length expressed in millimetres (e.g. M8-1.25×30 or M8×30). [citation needed] Tolerance classes defined in ISO 965-1 can be appended to these designations, if required (e.g. M500– 6g in external threads). External threads are designated by lowercase letter, g or h.

  9. Decibel - Wikipedia

    en.wikipedia.org/wiki/Decibel

    The decibel originates from methods used to quantify signal loss in telegraph and telephone circuits. Until the mid-1920s, the unit for loss was miles of standard cable (MSC). 1 MSC corresponded to the loss of power over one mile (approximately 1.6 km) of standard telephone cable at a frequency of 5000 radians per second (795.8 Hz), and matched closely the smallest attenuation detectable to a ...