## Planck's Constant

$E=hv$

Ryan Laureano 3I
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### Planck's Constant

I don't know if Professor Lavelle ever covered this, but out of curiosity how was planck's constant (h) derived?

Chem_Mod
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### Re: Planck's Constant

In principle, the Planck constant can be determined by examining the spectrum of a black-body radiator or the kinetic energy of photoelectrons.thats why we use it in formulas to calculate energy of photons. I dont think its important to know how it was derived. thats why we use it in formulas to calculate energy of photons.

Sahaj Patel Lec3DisK
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### Re: Planck's Constant

Even though how the constant was derived will not be in the scope of the class nor asked on exams, it was created by physicist Max Plank who determined the amount of energy a photon carries with the frequency of its electromagnetic waves. He called that amount of energy Planks Constant.

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### Re: Planck's Constant

Not too sure if this is the original derivation, but I believe in one of his audio-visual focus videos, he says that it can actually be derived empirically. If you plot the frequency of certain waves on the x-axis, and their corresponding energies on the y-axis, the slope of the resultant line will actually be Planck's constant.

Hope this helps :)

Yeprem
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### Re: Planck's Constant

Does anyone know if we have to remember what the planck's constant is or is it going to be provided to us?

Lorraine Jiang 2C
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### Re: Planck's Constant

Hi! I think professor Lavelle mentioned the Plank's constant was derived by plotting energy against frequency in a line graph. And the gradient of this graph will be Plank's constant. I think I have seen this in one of his modules, but I don't recall which one, I think it is not super important that we know how it is derived.

And I think professor Lavelle mentioned something about providing us some of the constants, but it is always better to just remember them!

Hope it helps!

SophiaNguyen_2L
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### Re: Planck's Constant

Yeprem wrote:Does anyone know if we have to remember what the planck's constant is or is it going to be provided to us?

I am 90% positive that the constant is given to us on a formula sheet or something of the like, but I think it'd be best to either ask a TA or Lavelle himself to make sure.

Yeprem
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Joined: Wed Sep 30, 2020 9:40 pm

thanks everyone