Planck constant


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Planck constant

(plank) Symbol: h . A fundamental constant with the value 6.626 076 × 10–34 joule seconds. According to quantum theory, electromagnetic radiation has a dual nature. Although many phenomena, including reflection and refraction, can be explained in terms of the wavelike nature of radiation, radiation may also be considered to be composed of discrete packets of energy called photons, so that it acts as a stream of particles. The particle-like and wavelike properties are related by Planck's law, in which the Planck constant is the constant of proportionality:
E = hv = hc
E is the energy of the photons and v and λ the frequency and wavelength of the wave; c is the speed of light in a vacuum. The Planck constant appears in most equations of quantum theory and quantum mechanics, including Planck's radiation law for black bodies.
References in periodicals archive ?
Since the meter is already defined (by the speed of light) and the second is defined (using a cesium atomic clock), fixing the value of the Planck constant will define what a kilogram is.
Smallness of Planck constant and vanishingly small value of information-entropy interaction force has negligibly small size, about [10.
Because of the quantum electrical standards involved, the ratio of the two power values results in a direct measurement of h, the Planck constant.
where h is the Planck constant, r is the radius of the sphere that is proportional to the velocity [upsilon] of the particle, and k is a proportionality constant.
A watt balance measurement conducted at the National Institute of Standards and Technology (NIST) is responsible for the most accurate measurement of the Planck constant, and has reduced the uncertainty in many physical constants.
The constant h (= m[upsilon][lambda]) turns out to be the Planck constant.
B] is the Boltzmann constant, h the Planck constant and T the supposed rapid thermodynamically equilibrated t-sliced locally flat instantaneous cosmological substratum temperature.
where, as is obvious, i= 1, while the complete momentum of the vortical tube (the Planck constant h) reduced to the radius of the electron can be determined as the vector recovered, on the basis of the projection, in the general way where i = 3.
2], perturb the PV simultaneously and lead to the Planck constant
Sections 2 through 6: show that the fine structure constant, the gravitational constant, and the Planck constant come from the PV; derive the free-space permittivities in terms of the PP parameters, showing that the free-space vacuum and the PV are one and the same; show that the previously unexplained force m[c.
In a stochastic-electrodynamic (SED) calculation [4] Puthoff derives the particle mass, the cutoff wavenumber (in terms of the speed of light, the Planck constant, and Newton's gravitational constant), and the gravitational force.
The interpretation is that cosmological expansion does not take place smoothly as in classical cosmology but by quantum jumps in which Planck constant increases at particular level of many-sheeted space-time and induces the expansion of space-time sheets.