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Homework Help: A Typo?

  1. Mar 25, 2010 #1
    A Typo?????

    1. The problem statement, all variables and given/known data

    The question is: Which of the following are units of momentum?
    The possible answers are: A. N x m B. kg x s/m C. kg x m^2/s D. J x s/m E. kg x m^2/s^2

    2. Relevant equations



    3. The attempt at a solution

    Is there a typo on this homework question? I thought that the units for momentum were kg x m/s, N x s, or kN x s. Am I wrong about this? Someone please help I think I'm going crazy lol.
     
  2. jcsd
  3. Mar 25, 2010 #2

    Doc Al

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    Staff: Mentor

    Re: A Typo?????

    There's no typo--one of the answers is correct. Check each one carefully.
     
  4. Mar 25, 2010 #3
    Re: A Typo?????

    What is a Joule in N, m, s
     
  5. Mar 25, 2010 #4
    Re: A Typo?????

    A joule is a unit. I dont understand what your asking me.
     
  6. Mar 25, 2010 #5

    Doc Al

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    Staff: Mentor

    Re: A Typo?????

    A Joule is a unit of what? What other units can be combined to equal a Joule?

    Example: A Newton is a unit of Force, but it's equivalent to kg-m/s^2. (Since F = ma.)
     
  7. Mar 25, 2010 #6
    Re: A Typo?????

    Well one Joule = 1 N x m... which is 1 kg x m^2/s^2 (i think). So is that the right answer? Im lost
     
  8. Mar 25, 2010 #7

    Doc Al

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    Staff: Mentor

    Re: A Typo?????

    Good.
    Go through each potential answer in turn and do a similar analysis in terms of kg, m, and s. Then you can compare its units with momentum units.
     
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