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Can someone tell me planck constant?

  1. Jun 28, 2014 #1
    Every time i see it it's different. I want the full planck constant(every number) and is there any proof for the constant?
  2. jcsd
  3. Jun 28, 2014 #2
    The Planck constant is:
    6.63 x 10^-34 J•s

    The symbol is "h". You will have different values depending on the units used. For example, Planck Constant is also:

    4.135667516(91) x 10^-15 in eV•s

    There are various proofs of the constant on the internet. A lot of the ones I see are experimental proofs.
  4. Jun 28, 2014 #3

    Simon Bridge

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    Nobody can comply with your request because nobody knows every digit - nobody can measure that accurately.
    You can look up the standard value online. I don't know of sources disagreeing, can you supply an example?
    There are many proofs for the constant - you can look those up too.
    Do you have reason to suspect that it may not be?

    Uh OK - in SI units: 6.62606957 × 10-34 m2 kg / s But in unified units it is 1.
    So, in that sense, you can know every digit ...

    AS for proofs - see:
  5. Jun 28, 2014 #4

    Ah I missed the "whole digit thing". Yeah, I agree with Simon! There isn't someone who actually knows every digit of the Planck constant.
  6. Jun 28, 2014 #5
    Thank you all for the answers
  7. Jun 28, 2014 #6


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    An extremely strange request.

  8. Jun 28, 2014 #7

    Simon Bridge

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  9. Jun 29, 2014 #8
    David J. Griffiths's Introduction to Quantum Mechanics defines hbar=h/(2pi) =1.05x10^(-34)J•s, and calls it "Planck's constant" before backing up and calling it "his original constant (h) divided by 2pi."
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