Constants of Nature

Yokagawa Electric Works has developed a thermometer based on the nuclear quadmpole resonance of potassium chlorate, usable over the range from —184 to 125°C. This thermometer makes use of the fundamental properties of the absorption frequency of the Cl nucleus, and its caUbration is itself a constant of nature. 

In summary, as a consequence of the factors considered in this and the preceding section, the atomic weights of only the 20 mononuclidic elements can be regarded as constants of nature . For all other elements variability in atomic weight is potentially possible and in several instances is known to occur to an extent which affects the reliability of quantitative results of even modest precision. 

Measuring and Using Numbers The slope calculated in step 5 on page 35 is an estimate of Planck s constant (h), one of the fundamental constants of nature. Recalling that one hertz is one cycle per second, or 1/s, the slope has units of J X s. Record your experimentally determined value of Planck s constant below and compare it to the accepted value of 6.626 X 10- 34 J s. 

Thinking Critically The form of your second graph is completely determined by two values the work function <, which is a property of the emitter material, and Planck s constant h, which is a fundamental constant of nature. The graph would look precisely the same if the lamp had been twice as bright. Explain why this observation leads to the conclusion that light has a particle-like aspect. 

If we set t= 1, this infinite series converges to the value 2.718271.. .. This number is a universal constant of nature (analogous to it) and is given the special symbol e. Thus the infinite series can be expressed as... 

Planck s constant (h) A universal constant of nature that relates the energy of a photon of radiation to the frequency of the emitting oscillator. Its numerical value is about 6.626 x ICh27 ergs/s. 

I returned to the University of Toronto in the summer of 1940, having completed a Master s degree at Princeton, to enroll in a Ph.D. program under Leopold Infeld for which I wrote a thesis entitled A Study in Relativistic Quantum Mechanics Based on Sir A.S. Eddington s Relativity Theory of Protons and Electrons. This book summarized his thought about the constants of Nature to which he had been led by his shock that Dirac s equation demonstrated that a theory which was invariant under Lorentz transformation need not be expressed in terms of tensors. 

If the result go = e would come out of a pure theoretical deduction, then the electronic charge would no longer be an independent constant of nature, but would become a quantized charge determined by Planck s constant and the velocity constant c of light, as indicated by Eq. (44). According to relation (43), this would then also apply to the product Mqiuq, whereas all quatitities Mq and mo have thus far not been deduced theoretically for the electron, but have been determined by measurements. 

Planck s constant Fundamental constant of nature equal to the eneigy of light divided by its frequency h = Elv == 6.626 X 10"34 J s. plasma A gas that is hot enough to contain free ions and electrons, as well as neutral molecules. 

Here q is the operator for the position of the particle and A, y are positive constants of nature. Show that this equation has the required form (5.6). In the -representation the last term is... 

Planck constant h A fundamental constant of nature with the value 6.626 08 X 10-34 J-s. plasma (1) An ionized gas. (2) In biology, the colorless component of blood in which the red and white blood cells are dispersed. 

Catalogue of Spectral Data and Physical Constants of Naturally... 

LThat is, only fundamental constants of nature (Planck constant, elementary charge, and electronic and nuclear masses) have been used as input in the calculation. 

Grum-Grzhimailo, S. V., Anikina, L. I., Belova, E. N. Tolstikhina, K. I. (1955) Curves of spectral absorption and other physical constants of natural micas. Mineral. Sbomik. Lvov Geol. Obshch., 9, 90-119. 

Certain units not part of the SI are so widely used that it is impractical to abandon them (e.g., liter, minute, and hour) or are so well established that the International Committee on Weights and Measures has authorized their continued use (e.g., bar, curie, and angstrom). In addition, quantities that are expressed in terms of the fundamental constants of nature, such as elementary charge, proton mass, Bohr magneton, speed of light, and Planck constant, are also acceptable. However, broad terms such as atomic units are not acceptable, although atomic mass unit, u, is acceptable and relevant to chemistry. 

Compare Clarke, Constants of Nature, 2nd ed., Washington, 1888, 1, 126 Schroder, Dichtigkeitsmessungen, Heidelberg, 1873. 

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