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How to write joules per metre squared per second

  1. Nov 10, 2011 #1
    This was a question I had in another post, but the main topic was on a similar but different issue...

    If I had the dimensions joules per metre squared per second (e.g. like for a solar panel), how would I write that?

    I've been told

    But I get [tex]\frac{J}{m^2s}[/tex]

    Why is it this:
    [tex]\frac{J}{1} \times \frac{s}{m^2}[/tex]
    And not:
    [tex]\frac{J}{m^2} \times \frac{1}{s} [/tex]

    I'm grouping joules over metre squared together whereas everyone I've talked to does the first one - why? And am I wrong for saying 'per metre per second'? Should time come first? What is the convention here?

    Thank you
  2. jcsd
  3. Nov 10, 2011 #2
    If you mean that each second you are receiving 'x' joules of energy over each square meter then [itex] \frac{J}{m^2 s} [/itex] are the correct units.
  4. Nov 10, 2011 #3
    I agree with JHamm... you have it correct J/m^2s not Js/m^2
    It means Watts per square metre which makes sense when talking about solar panels.
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