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Homework Help: Confused About Power Density Units

  1. Aug 29, 2015 #1
    1. The problem statement, all variables and given/known data

    So I saw a unit "W/(g2 cm3)"
    And I'm pretty sure it's about power density...and I understand what W/cm3 is. It's watts per cubic centimeter...but what does the g mean? grams? If so, how does that fit in? :/
  2. jcsd
  3. Aug 29, 2015 #2


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    Sure it wasn't ##(W/g^2)/cm^3##?
  4. Aug 29, 2015 #3
    W/(g2 cm3) is the exact form
  5. Aug 29, 2015 #4


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    Can you give us any context?
  6. Aug 29, 2015 #5


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    That's okay, it's technically the same thing. I've only ever seen it written in this form in relation to power densities:


    Normally in reference to maximum power densities.

    Yes, what is the context you saw it in?
  7. Aug 29, 2015 #6
    There are other places where I saw mW instead of W, what does it mean though?

    -It is regarding maximum power densities
  8. Aug 29, 2015 #7


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    Last edited: Aug 29, 2015
  9. Aug 29, 2015 #8
    Not mW I knew that, I meant the rest of it...like could you say it framed like "x cubic centimeters" or like full meaning in practical terms...
    Like what does the g mean D:
    Last edited: Aug 30, 2015
  10. Aug 30, 2015 #9


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    Where? In what reference? In what context?

    Without that sort of information we can't answer your question.

    Also, is this homework? If so, you should be filling out the complete homework template, including an actual problem. What you've given isn't a problem, it's just a question.
  11. Aug 30, 2015 #10


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    Here's a paper that references it,


    Figure 4. Has units ##(W/g^2)/cm^3##

    It almost always has something to do with vibration energy harvesting, I don't know that much about it. Just remember seeing it once before.
  12. Aug 30, 2015 #11
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