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Homework Help: Hooke's Law Query

  1. Mar 19, 2005 #1
    Morning peoples,

    I have a query about Hooke's Law. :confused: I have a problem which asks me to calculate the spring constant (k). I know how to do it, but my question is when I use the formula mg/x can mass be in newtons or does it have to be in kg?

    Looking forward to your answers. Thanks! :smile:
  2. jcsd
  3. Mar 19, 2005 #2


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    Science Advisor

    Mass is never in Newtons. Newtons is a unit of force (remember F=ma?). That being said, if you want to redefine your equation by saying

    k = (mg)/x = F/x

    Then you can use your force directly.
  4. Mar 19, 2005 #3
    Thanks for clarifying. Sometimes its hard to remember the simple stuff, you know? Thanks Fred. :smile:
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