reciprocity law

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Related to reciprocity law: Quadratic reciprocity law

Bun·sen-Ros·coe law

(bŭn'sĕn ros'kō),
in two photochemical reactions, for example, the darkening of a photographic plate or film, if the products of the intensity of illumination and the time of exposure are equal, the quantities of chemical material undergoing change will also be equal; the retina for short periods of exposure obeys this law.

reciprocity law

Any milliamperage multiplied by an exposure time setting that gives the same milliamperage-second outcome should give the same relative density to an image. However, this law is dramatically affected by the image receptor response curve, esp. when it is not a 45° linear curve. In radiographic intensifying film and screen technologies, the reciprocity law does not hold at long exposure times because of the reversal of the D log E response curve.
See also: law


Robert W., German chemist and physicist, 1811-1899.
Bunsen burner - a gas lamp giving a very hot but only slightly luminous flame.
Bunsen solubility coefficient - the milliliters of gas STPD dissolved per milliliter of liquid and per atmosphere (760 mmHg) partial pressure of the gas at any given temperature.
Bunsen-Roscoe law - in two photochemical reactions, if the product of the intensity of illumination and the time of exposure are equal, the quantities of chemical material undergoing change will be equal. Synonym(s): reciprocity law; Roscoe-Bunsen law
Roscoe-Bunsen law - Synonym(s): Bunsen-Roscoe law
References in periodicals archive ?
Using the high irradiance UV source in the NIST SPHERE, experiments have been carried out to validate the reciprocity law for a non-pigmented, non-UV stabilized acrylic-melamine coating exposed to different broad band irradiance levels at ambient temperature and humidity, as well as an amine-cured epoxy exposed to spectral UV irradiance levels at elevated temperature.
The potential impact of both the additivity and reciprocity laws on the polymeric materials community is tremendous.
From the 1880s through the early part of the 20th century, the majority of reciprocity law experiments were performed on photographic materials.
Bunsen and Roscoe (1) are credited with deriving and conducting the first reciprocity law experiments on photographic materials.
Deviations from the reciprocity law are called reciprocity law failure.
Since the reciprocity law depends only on total absorbed energy, validation of the reciprocity law for a material can have many experimental manifestations, as shown in Figure 1.
7-11) Reciprocity law failures were most commonly observed for experiments conducted at either very low or very high irradiance levels.
Note that when p = 1, Schwarzschild's law and the reciprocity law are identical and hence, Schwarzchild's law is a generalization of the reciprocity law.
13) When the log It versus log I plot is linear and parallel to the abscissa, then the reciprocity law is assumed to be obeyed.
669, and polycarbonate was shown to obey the reciprocity law with a p-coefficient of 1.
Taking the standard deviations into account, the linear regression lines plotted through the data points in these figures were generally observed to be parallel to the abscissa, indicating that the reciprocity law is obeyed for these modes of damage.
Justice Souter asked whether reciprocity laws between states were unconstitutional.