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Homework Help: Ns and N/s

  1. Aug 29, 2006 #1

    danago

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    Hey. Im having a little trouble differentiating between newtons per second ([itex]N s^{-1}[/itex]) and newton seconds (N s). I know that N/s is a measurement of a certain number of newtons over a period of 1 second, but could someone please explain what a newton second is?

    Thanks,
    Dan.
     
  2. jcsd
  3. Aug 29, 2006 #2
    Ns is a unit used to quantify momentum.
     
  4. Aug 29, 2006 #3

    danago

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    momentum? I thought momentum was usually measured in kg m/s? ISnt Ns used to measure impulse?
     
  5. Aug 29, 2006 #4
    Well, N = kg m / s^2 and Ns ends up being kg m / s.
     
  6. Aug 29, 2006 #5

    berkeman

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    So what are units of N/s used for? N*m/s would be power, so N/s is power per distance? Where did you see these units pop up, danago?
     
  7. Aug 30, 2006 #6

    danago

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    For impulse. Since [itex]I=F \Delta t[/itex], therefore, its unit would be Ns wouldnt it?
     
  8. Aug 30, 2006 #7

    Hootenanny

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    Yes, Newton-seconds is the unit of impulse. However, I can see where the confusion arose with respect to momentum, since the change in momentum is equal to the impulse.
     
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