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Homework Help: Kilogram Newtons (Extremely Easy Question!)

  1. May 17, 2006 #1
    Very sorry, but I just don't know..

    If there is a 5kg load on an object, let's say a book on a table.. what is it's force in kgN? Is it 5kg x 9.8?!
     
  2. jcsd
  3. May 17, 2006 #2

    Doc Al

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    Staff: Mentor

    Yes, the weight of a 5kg mass is about 5*9.8 = 49 Newtons.
     
  4. May 18, 2006 #3
    maybe he is getting at the difference between kgm and kgf (kilogram mass and kilogram force)?
     
  5. May 18, 2006 #4

    Doc Al

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    Staff: Mentor

    Good point.

    If by "5 Kg load" you mean the weight of an object whose mass is 5 Kg, then find the force via w = mg. The load equals (approximately) 5*9.8 = 49 N as I stated above.

    On the other had, if by "5 Kg load" you really meant a load (force) of 5 kgf (Kilogram-force, a unit of force, not mass), then convert to standard (SI) units of force (Newtons) using the definition of 1 kgf = 9.80665 N.

    Of course, for many purposes either one is close enough.

    Note: kgN is not a unit (that I am aware of). Mass is measured in kg (also called kgm for kilogram-mass); force is measured in N (or kgf, for kilogram-force).
     
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