What does the unit "Js" of the Planck constant mean?

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Discussion Overview

The discussion revolves around the meaning of the unit "Js" associated with Planck's constant, exploring its implications in quantum mechanics and its role in defining physical quantities. Participants engage in clarifying misconceptions about the nature of Planck's constant and its units.

Discussion Character

  • Conceptual clarification
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants assert that Planck's constant is not a measure of energy, emphasizing that its units are "Js" (Joule times second).
  • Others highlight that the unit "Js" suggests a relationship to phase space volumes and is indicative of fundamental constants in nature.
  • A few participants reference external sources, such as Wikipedia and previous threads, to support their points about the significance of Planck's constant in quantum mechanics.
  • There is a contention regarding the interpretation of the unit "Js," with some participants questioning the adequacy of online searches for its meaning.
  • One participant notes that the Planck constant relates a photon's energy to its frequency, indicating its fundamental role in quantum mechanics.

Areas of Agreement / Disagreement

Participants generally disagree on the interpretation of Planck's constant and its units, with multiple competing views presented regarding its significance and implications in physics.

Contextual Notes

Some limitations in understanding arise from the dependence on definitions of energy and action, as well as the context in which Planck's constant is applied. There are unresolved questions about the implications of the unit "Js" in relation to other physical concepts.

Fouzan Alaa Almassry
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TL;DR
what means unit j.s in plank constant As Planck's constant is the smallest unit of energy so what this unit j.s
what means unit j.s in plank constant As Planck's constant is the smallest unit of energy so what this unit j.s
 
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Have you tried to google what “Js” stands for? What did you find?

Also Plancks constant is not an energy (as you would discover by finding out what the ”J” in Js means).
 
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Well, first of all the unit Js (Joule times second) tells you that ##\hbar## cannot indicate an energy to begin with, because the unit of energy within the SI is J and not Js.

As I've said very many times in the last few days, the unit Js also gives a hint, what ##\hbar## might indicate. It's a fundamental constant of nature and thus provides a natural measure for some quantity with the unit Js, and that's the same as the unit length times momentum. In turn this indicates that it's the natural measure for phase space volumes, and this turns indeed out to be correct when you consider statistical physics of a many-body system.
 
Dr.AbeNikIanEdL said:
Have you tried to google what “Js” stands for? What did you find?

Also Plancks constant is not an energy (as you would discover by finding out what the ”J” in Js means).
He searched on Google, but did not give an adequate answer and did not give the meaning of this unit
 
PeroK said:
Planck's constant is important in QM but it is not the smallest unit of energy. It's not even a measure of energy. As you note, its units are ##Js##.

There was a thread about this recently:

https://www.physicsforums.com/threads/does-the-energy-6-626x10-34j-have-any-special-meaning.993063/
Dr.AbeNikIanEdL said:
Have you tried to google what “Js” stands for? What did you find?

Also Plancks constant is not an energy (as you would discover by finding out what the ”J” in Js means).
The Planck constant, or Planck's constant, is the quantum of electromagnetic action that relates a photon's energy to its frequency. The Planck constant multiplied by a photon's frequency is equal to a photon's energy. The Planck constant is a fundamental physical constant denoted as {\displaystyle h}
h
, and of fundamental importance in quantum mechanics. In metrology it is used to define the kilogram in SI units.[2]
 
Fouzan Alaa Almassry said:
He searched on Google, but did not give an adequate answer and did not give the meaning of this unit

Who is "he"? If you mean you searched, the word "he" doesn't make sense. If you mean you think @Dr.AbeNikIanEdL was supposed to search Google and come up with the answer for you, no, that's not what he was saying. He was saying you should do the searching, and then post again here if you have questions about what you find.
 
Fouzan Alaa Almassry said:
The Planck constant, or Planck's constant, is the quantum of electromagnetic action that relates a photon's energy to its frequency.

That's the physical problem that originally motivated Planck to come up with his constant, but its physical applications are not limited to that.

Fouzan Alaa Almassry said:
The Planck constant multiplied by a photon's frequency is equal to a photon's energy. The Planck constant is a fundamental physical constant denoted as {\displaystyle h}, and of fundamental importance in quantum mechanics. In metrology it is used to define the kilogram in SI units.[2]

Do you have a question about any of these things?
 
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  • #10
J = Joule
s = second
J . s = Joule . second
 
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