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What is this unit?

  1. Dec 29, 2011 #1
    Change the forum if this is in the wrong place but I was doing some math (multiplying hertz and watts) and I came with 4.8912 × 10^12 m^2 kg / s^4, I don't know what unit that is, so can anybody tell me if there even is one?
  2. jcsd
  3. Dec 29, 2011 #2
    there is no known physical quantity with those dimensions.
  4. Dec 29, 2011 #3


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    Staff: Mentor

    [tex]Watt = Joule/s = kg*m^2*s^{-3}[/tex]

    [tex]Hertz = s^{-1}[/tex]

    So your units are correct. Basically it's Joules per s^2, or Watts per second.

    But as pointed out, it is unusual to multiply power and frequency. What was the calculation for?
  5. Dec 30, 2011 #4
    I meant to divide hertz and watts and I would get 2 122.91667 m^-2 * kg^-1 * s^2 so now I think my question truly is what is that unit
  6. Dec 30, 2011 #5


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    Staff: Mentor

    As asked, what are you trying to accomplish? It almost seems like you are doing blind math, hoping to stumble on something interesting.
    Last edited by a moderator: Dec 30, 2011
  7. Jan 1, 2012 #6
    I was trying to find how far one photon can go like with a radio transmitter, how far could one of those photons could go. And now I found I did not have enough information to do these calculations.
  8. Jan 2, 2012 #7
    There's no limit to how far a photon can go. But I'm not sure you can come to a conclusion like that by doing dimensional analysis. Sometimes interesting things can pop out though.
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