enow.com Web Search

Search results

1. Results from the WOW.Com Content Network

2. List of measuring instruments - Wikipedia

   en.wikipedia.org/wiki/List_of_measuring_instruments

   Lux meter for measuring illuminance, i.e. incident luminous flux per unit area; Luminance meter for measuring luminance, i.e. luminous flux per unit area and unit solid angle; Light meter, an instrument used to set photographic exposures. It can be either a lux meter (incident-light meter) or a luminance meter (reflected-light meter), and is ...

3. Astronomical system of units - Wikipedia

   en.wikipedia.org/wiki/Astronomical_system_of_units

   The speed of light in IAU is the defined value c 0 = 299 792 458 m/s of the SI units. In terms of this speed, the old definition of the astronomical unit of length had the accepted value: [ 3 ] 1 au = c 0 τ A = ( 149 597 870 700 ± 3 ) m, where τ A is the transit time of light across the astronomical unit.

4. Multimeter - Wikipedia

   en.wikipedia.org/wiki/Multimeter

   Analog multimeter Digital multimeter. A multimeter (also known as a volt-ohm-milliammeter, volt-ohmmeter or VOM) [1] is a measuring instrument that can measure multiple electrical properties. [2] [3] A typical multimeter can measure voltage, resistance, and current, [4] in which case can be used as a voltmeter, ohmmeter, and ammeter.

5. Speed of light - Wikipedia

   en.wikipedia.org/wiki/Speed_of_Light

   A method of measuring the speed of light is to measure the time needed for light to travel to a mirror at a known distance and back. This is the working principle behind experiments by Hippolyte Fizeau and Léon Foucault. The setup as used by Fizeau consists of a beam of light directed at a mirror 8 kilometres (5 mi) away. On the way from the ...

6. Foucault's measurements of the speed of light - Wikipedia

   en.wikipedia.org/wiki/Foucault's_measurements_of...

   The rotational speed of the mirror could not be sufficiently accurately measured to determine the absolute speeds of light in water or air. With a rotational speed of 600-800 revolutions per second, the displacement was 0.2 to 0.3 mm. [5]: 128–129

7. Delta-v - Wikipedia

   en.wikipedia.org/wiki/Delta-v

   Delta-v (also known as "change in velocity"), symbolized as and pronounced /dɛltə viː/, as used in spacecraft flight dynamics, is a measure of the impulse per unit of spacecraft mass that is needed to perform a maneuver such as launching from or landing on a planet or moon, or an in-space orbital maneuver.

8. Escape velocity - Wikipedia

   en.wikipedia.org/wiki/Escape_velocity

   Escape speed at a distance d from the center of a spherically symmetric primary body (such as a star or a planet) with mass M is given by the formula [2] [3] = = where: G is the universal gravitational constant (G ≈ 6.67×10 −11 m 3 ·kg −1 ·s −2)

9. Michelson–Morley experiment - Wikipedia

   en.wikipedia.org/wiki/Michelson–Morley_experiment

   For instance, the Fizeau wheel could measure the speed of light to perhaps 5% accuracy, which was quite inadequate for measuring directly a first-order 0.01% change in the speed of light. A number of physicists therefore attempted to make measurements of indirect first-order effects not of the speed of light itself, but of variations in the ...