Results 241 to 250 of about 178,977,434 (287)

A Pedagogical Measurement of the Velocity of Light

American Journal of Physics, 1969
An inexpensive, simple, easily constructed and convincing technique is described both for demonstrating that the speed of light is finite, and for measuring its value. All that is required is about $40 and a good oscilloscope. Detailed instructions and experimental results are given, and it is found that c = (29.8±0.6) cm/nsec.
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Final Measurements of the Velocity of Light

Journal of the Optical Society of America, 1941
Improvements in the apparatus formerly used include the use of an eleven-stage electron multiplier tube, the control of the transmitter frequency by the laboratory standard, the substitution of a 1000-watt water-cooled mercury arc for the light source, a new type of Kerr cell, changes in the mirror supports and base line measurements, and the use of an
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Doppler Velocity Measurements using White Light

Nature, 1971
VELOCITY measurements, based on observations of the Doppler shift in frequency of radiation scattered by moving objects, have been made using various optical arrangements (for example, refs. 1–6), The coherency requirements of the illuminating radiation have been considered by Rudd5, who concluded that conventional (that is, not laser) light sources ...
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Reflections on the problem of measuring the velocity of light

Acta Physica Academiae Scientiarum Hungaricae, 1964
The phenomena connected with the propagation of light are analysed with the purpose of re-examining as to what conclusions can be drawn from the relevant experiments. It is found, that a very clear picture can be obtained supposing—contrary to the usually accepted view—that electromagnetic waves possess a carrier which may be taken as the ether.
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Interferometric Method of Velocity of Light Measurement

Applied Optics, 1963
An association of interferometric methods in the 3.2-cm microwave and visible-light optical domains is now being used for the measurement of the velocity of light in terms of primary atomic constants, an atomic clock for the frequency and a light source (Hg 198, Kr 86, optical maser) for the length.
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VIII.—A Measurement of the Velocity of Light in Water

Proceedings of the Royal Society of Edinburgh. Section A. Mathematical and Physical Sciences, 1944
In the Proc. Roy. Soc. Edin. (Houstoun, 1941) I described a new method of measuring the velocity of light. Owing to the difficulties of the times progress has been slow, but I have now succeeded in measuring the velocity of light in water and communicate the result here.Previous Measurements.—Every elementary textbook on Light explains how Newton's ...
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White-light speckle method of measurement of flow velocity distribution

Applied Optics, 1982
A white-light speckle technique for measurement of flow velocities is described. The speckle patterns are formed by incoherent light at the image plane of the fluid illuminated section. The convection flow generated in a rectangular cell filled with silicone oil is studied with this technique.
E, Bernabeu, J C, Amaré, M P, Arroyo
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Determination of velocity gradients with scattered light cross-correlation measurements

Applied Optics, 1983
The space-time correlation function of the intensity of light scattered off a medium with a constant velocity gradient has been calculated. One property, in particular, of this correlation function, which may be referred to as speckle motion or speckle flow, enables an experimental determination of the tensor components of the velocity gradient ...
C, Keveloh, W, Staude
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XLII. A New Effort to Measure the Velocity of Light†

Journal of Electronics and Control, 1957
The value of the group velocity of light in terms of a distance pro time is explained and a practicable method for its determination is proposed.
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The band spectrum method of measuring the velocity of light

Journal of Molecular Spectroscopy, 1965
Abstract Work on the band spectrum method of measuring the velocity of light is summarized and brought up to date. It is shown how improvements in both infrared measurements and developments in microwave techniques have resulted in an increase in precision in the determination of c by the band spectrum method.
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