Scientists are gathering to change the weight of one kilogram in a more stable unit of measurement
علماء يجمعون على تبديل وزن الكيلوغرام الواحد بوحدة قياس أكثر ثباتا
In the French city of Sevres, west of Paris at the International Bureau of Weights and Measurements and under three glass lanterns, lies one of the most indispensable units in our daily lives, kilograms. , Today scientists say that this metal block has been referred to retire.
The mass that weighs exactly 1,000 grams has for many decades been the only reference for all countries in the world using the metric system. Once every 40 years scientists from each country come to Sever to compare it with a kilogram called Prototype K to make sure that There were no fines on their clothes, and nothing was missing from them.
But this weight mass, made of a platinum and iridium alloy that has been adopted for 129 years, is flawless. It is constantly exposed to the accumulation of dust atoms, which increases its weight. Its cleaning also causes erosion of platinum atoms, which results in an opposite result. Nevertheless, it has survived among all seven metric units in the metric world as the last real measuring unit still used to calibrate world kilograms.
Fate is a must
As the science and technology of measuring instruments progressed, the other six measurement units (distance, second, time, quantity and ampere for power and kevin for temperature and brightness for power of illumination) underwent a radical change, replaced by real comparison models to mathematical comparison models. For example, Metal ruler found at the International Bureau of Weights and Measurements at 0 ° C The 1960 was based on a more stable measurement based on the length of the number of light waves emanating from the radioactive Krypton 86 atom, and in 1983 it became dependent on the speed of light in the vacuum.
Next week, the kilogram unit will officially join its counterparts, and will be voted on by scientific figures from 57 countries at the General Conference of weights and measurements in Versailles. Although this change has been tentatively approved, the aim of the vote is to ease the tension that may result from what some have called a "revolution in the world of measurement units".
"I've been thinking about this for the rest of my life as a scientist," says Stefan Schlaminger, a physicist at the National Institute of Standards and Technology at The Guardian.
In recent history, the kilogram has undergone a series of experiments that it attempted to replace with a unit derived from a standard constant such as the Avogadro Project, which was determined by a ball weight made of a pure silicon element of exactly 93.6 millimeters, based on the atomic weight of silicon and the unchanged number of avogadro. But it was also a question.
In 2003, a German research center identified the kilogram by accumulating ions (atoms or charged particles) using electrodes and a constant electric current.
Scientists now determine the new kilogram by means of a mass derived from a number that is rooted in quantum physics. It is Planck's constant, using a complex balance called a "cable balance" to calibrate one kilogram by comparing it with a specific electromagnetic force rather than using a physical mass.
"The greatest satisfaction for me would be the completion of the historical course that began with the French Revolution," says Schlamminger, adding that "the idea was to have a single measurement system for all times and for all people." We have always had problems with the stability of the kilogram unit, To all people at all times, and the Planck constant is unchanging, it is always the same and available to all and its value is derived from the fabric of the universe in which we live. "
https://arabic.euronews.com/2018/11/12/scientists-vote-to-replace-traditional-ibwm-kilogram-with-electronically-measured-unit
Thank you, Dr. Jari, for a very informative question and a prelude. This is exciting improvement in measurement science but diffusion of this innovation will take a long time. General Conference on Weights and Measures, the supreme authority on the subject has introduced Planck constant, to redefine kilogram in terms of the second and the speed of light. The International Bureau of Weights and Measures (BIPM) has approved this measure, in an attempt to address issues with KG as a measure.
Thank you, Dr. Jari, for a very informative question and a prelude. This is exciting improvement in measurement science but diffusion of this innovation will take a long time. General Conference on Weights and Measures, the supreme authority on the subject has introduced Planck constant, to redefine kilogram in terms of the second and the speed of light. The International Bureau of Weights and Measures (BIPM) has approved this measure, in an attempt to address issues with KG as a measure.
The dimensionality of the Planck constant h is J s (Joule, J, times second, s, or energy times time): [h] = J s. In the SI units, [J] = m kg s-2, metre times kilogram times inverse of second squared. Thus, when kg changes, h changes accordingly. The CODATA recommended values for h:
In 2014 [1]: h = 6.626 070 040(81) × 10−34 J s.
In 2018 [2]: h = 6.626 070 15 × 10−34 J s.
[1] https://www.nist.gov/sites/default/files/documents/pml/div684/fcdc/wall2014.pdf
[2] https://www.bipm.org/utils/en/pdf/si-revised-brochure/Draft-SI-Brochure-2018.pdf (see Table 1 on page 11).
In the 4th. Of December 2018 I have presented a presentation here in RG platform about this topic, so for more information about this topic, you may find this lecture.
Emad
Planck's constant is a physical constant with the symbol h, which is used to describe quantum as "the smallest amount of energy", thus playing the main role in quantum mechanics. His discovery dates back to the German world of Max Planck in 1900. This constant corresponds to another value which is the value of this constant divided by 21 and a symbol h and the term "ash bar" is used. In this case it is called the fixed plank constant, which is sometimes called the Dirac constant relative to the world Paul Dirac.
Planck's constant is the smallest unit of energy multiplied by the time unit (second). It is a physical constant. It is used to describe quantum as the "smallest amount of energy", thus playing the main role in quantum mechanics. His discovery dates back to the German world of Max Planck in 1900.
The question is a nice opportunity for me to learn about this interesting topic.
Regards
Planck's constant, symbolized h, relates the energy in one quantum "Quantum is the Latin word for an amount and, in modern understanding, means the smallest possible discrete unit of any physical property, such as energy or matter. Quantum came into the latter usage in 1900, when the physicist Max Planck used it in a presentation to the German Physical Society." of electromagnetic radiation to the frequency of that radiation. In SI, the constant is equal to approximately 6.626176 x 10-34 joule-seconds. In the centimeter-gram-second (cgs) or small-unit metric system, it is equal to approximately 6.626176 x 10-27 erg-seconds.
Please take a look at this useful link.
https://www.quora.com/What-are-the-units-of-Plancks-constant
Receiving and thanking for the contributution of informative information .
The Planck constant is relates the energy in one quantum (photon) of electromagnetic radiation to the frequency of that radiation.
The Planck constant is a physical constant that is the quantum of electromagneticaction, which relates the energy carried by a photon to its frequency.
https://en.wikipedia.org/wiki/Planck_constant
Planck postulated that electromagnetic energy at a given frequency could only be emitted in discrete amounts, or quanta, whose energy is proportional to h, now known as the Planck constant.
Please see the link below:
https://www.nist.gov/si-redefinition/kilogram-mass-and-plancks-constant
Interesting question that provoked valuable informations from our RG colleagues
Max Planck (1858–1947) originally had no idea how widely applicable his notion of the "quantum" would become, including its role in measuring mass. He conceived it in the context of a stubborn problem in 19th-century physics: A leading theory of the day nonsensically predicted that certain objects would radiate an infinite amount of power when they released electromagnetic radiation at high frequencies (and thus short wavelengths, that is, toward the ultraviolet part of the spectrum in the graph above) — a situation that became known as the "ultraviolet catastrophe."
https://www.nist.gov/si-redefinition/kilogram-mass-and-plancks-constant
The link below explained that
https://whatis.techtarget.com/definition/Plancks-constant.
Member States of the International Bureau of Weights and Measures agreed to redefine the kilogram on the basis of a small but not insignificant value called the Planck constant.
Planck's constant unit: joule-seconds
Planck's constant, symbolized h, relates the energy in one quantum (photon) of electromagnetic radiation to the frequency of that radiation. In the International System of units (SI), the constant is equal to approximately 6.626176 x 10-34 joule-seconds.
Valuable contributions by respected RG members on this discussion
In the International System of units (SI), the constant is equal to approximately 6.626176 x 10-34 joule-seconds.
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