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Prentice's rule, named so after the optician Charles F. Prentice, is a formula used to determine the amount of induced prism in a lens: = where: P is the amount of prism correction (in prism dioptres) c is decentration (the distance between the pupil centre and the lens's optical centre, in millimetres)
A correction must also be made for fractionation. The fractionation correction converts the 14 C / 12 C ratio for the sample to the ratio it would have had if the material was wood, which has a δ 13 C value of -25‰. This is necessary because determining the age of the sample requires a comparison of the amount of 14
In the above formula for r s , if we put = / (Snell's law) and multiply the numerator and denominator by 1 / n 1 sin θ t , we obtain r s = − sin ( θ i − θ t ) sin ( θ i + θ t ) . {\displaystyle r_{\text{s}}=-{\frac {\sin(\theta _{\text{i}}-\theta _{\text{t}})}{\sin(\theta _{\text{i}}+\theta _{\text{t}})}}.}
A dioptre ( British spelling) or diopter ( American spelling ), symbol dpt, is a unit of measurement with dimension of reciprocal length, equivalent to one reciprocal metre, 1 dpt = 1 m−1. It is normally used to express the optical power of a lens or curved mirror, which is a physical quantity equal to the reciprocal of the focal length ...
For example, for decays of 132 Cs, 98.1% are ε ( electron capture) or β + ( positron) decays, and 1.9% are β − ( electron) decays. The partial decay constants can be calculated from the branching fraction and the half-life of 132 Cs (6.479 d), they are: 0.10 d −1 (ε + β +) and 0.0020 d −1 (β − ).
For example, such a regulation might limit the concentration of NOx to 55 ppmv in a dry combustion exhaust gas corrected to 3 volume percent O 2. As another example, a regulation might limit the concentration of particulate matter to 0.1 grain per standard cubic foot (i.e., scf) of dry exhaust gas corrected to 12 volume percent CO 2.
Applications. There are many different effective medium approximations, each of them being more or less accurate in distinct conditions. Nevertheless, they all assume that the macroscopic system is homogeneous and, typical of all mean field theories, they fail to predict the properties of a multiphase medium close to the percolation threshold due to the absence of long-range correlations or ...
The formula for decay correcting is: = where is the original activity count at time zero, is the activity at time "t", "λ" is the decay constant, and "t" is the elapsed time.
The application of Euler's continued fraction formula is straightforward: e x = 1 1 − x 1 + x − 1 2 x 1 + 1 2 x − 1 3 x 1 + 1 3 x − 1 4 x 1 + 1 4 x − ⋱ . {\displaystyle e^{x}={\cfrac {1}{1-{\cfrac {x}{1+x-{\cfrac {{\frac {1}{2}}x}{1+{\frac {1}{2}}x-{\cfrac {{\frac {1}{3}}x}{1+{\frac {1}{3}}x-{\cfrac {{\frac {1}{4}}x}{1+{\frac {1}{4 ...
The formula for Volume Correction Factor is commonly defined as: V C F = C T L = exp { − α T Δ T [ 1 + 0.8 α T ( Δ T + δ T ) ] } {\displaystyle VCF=C_{TL}=\exp\{-\alpha _{T}\Delta T[1+0.8\alpha _{T}(\Delta T+\delta _{T})]\}}