Measure Planck's constant without universal constants

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Heisenberg_white
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Homework Statement
Suggest a method to measure h (Planck's constant) without using the value of any other universal constant.
Relevant Equations
h = 6.626e-34
I am not getting any ideas to solve this without the universal constants. The method that I want to use invloves the speed of light, which is a universal constant.
 
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Thanks a lot for replying!
In the experiment, we used LEDs emitting different colors & found out their barrier potentials, from which we calculated the Planck's constant. Energy, E = eV = hν ( where, e - energy of an electron; V - barrier potential). from this we get V = hc/eλ. and in turn, h = eVλ/c.
But anyway, none of this is related to the question that I have asked. My question was asked as a supplementary question by my professor. This is just to tell you how the experiment was conducted.

Thank you again! :)
 
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Is this question asked in the context of the "new SI", i.e., the redefinition of the international system of units through natural constants. Then the answer is in the following Physics Today article:

https://physicstoday.scitation.org/doi/10.1063/PT.3.4472

Of course you cannot measure ##h## in the described (gedanken) experiment without referring to ##\nu_{\text{Cs}}## (defining the second) and ##c## (defining, together with the second, the metre). All units are interconnected, starting with ##\nu_{\text{Cs}}## to define the second.
 
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