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Joule Watt second = How many Plank?

  1. Aug 15, 2011 #1
    I hope someone can help me find quantity of electricity.

    how big is a Planck? In other words, how many Plancks per one second (unit time) equal one Watt-second (unit energy) at 60 hz (377 radian)?
  2. jcsd
  3. Aug 15, 2011 #2
    What's a Planck?
  4. Aug 15, 2011 #3
    Planck Q ( Max Planck - E = hν) charge of the electron for electrostatic planck unit
    Last edited: Aug 15, 2011
  5. Aug 15, 2011 #4


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    dimensional analysis:

    h = planck's constant
    n = number of "plancks"

    units(h/s) = Ws

    n("plancks"/s)= 1 W/60 Hz

    n = 1.67e-2 Ws^2/h

    n = 2.5*10^31
  6. Aug 15, 2011 #5
    are you sure?
    1 Ws (watt second) = 2.5*10^31n
  7. Aug 15, 2011 #6


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    You seem to be confused by some of the terminology. The electron charge is irrelevant in the formula E=hv, which relates the energy of a photon (E) to its frequency (v) via Planck's constant (h). Physicists just call E "the energy of a photon", not "a Planck" as far as I'm aware.

    At a frequency of 60 Hz, a photon would have the energy
    [tex]E=h \nu = 6.63 \cdot 10^{-34} \text{ J/Hz} \ \cdot 60 \ \rm{Hz} = 4.0 \cdot 10^{-32} \text{ J, or} \ 4.0 \cdot 10^{-32} \ \rm{W \cdot s}[/tex]
    However, apart from serving as an academic exercise, I know of no practical value in thinking about photon energies when dealing with everyday 60 Hz phenomena.

    OR ... maybe you really are asking about charge, and how many fundamental charge units are flowing in an electric circuit?

    (EDIT added) OR ... do you want to know how many Joules are equivalent to one Planck energy? Answer: 1.956 × 109 J. For details, see:

    Last edited: Aug 15, 2011
  8. Aug 15, 2011 #7
    My hobbyist research is to convert house current into electrostatic energy (ultrasonic force) to aid house plant in photosynthesis (dissociation of water) during winter. This was a peculiar interest to plant enthusiasts of early 20th century. I am implementing modern apparatus of my own design and theories presented Harvey F. Lodish in Molecular cell biology. I wish to employ natural Planck unit as measurement standard.

    My confusion is with measurements of house electricity being expressed in electron, whereby lepton is conveyed differently by publications Electricity and Matter, Recent Researches Into Electricity by J.J. Thompson.
    Last edited: Aug 15, 2011
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