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I need a little info please

  1. Aug 30, 2006 #1
    is there any formulas for a spring, or any way at all to calculate the weight needed to compress a spring, or do you just have to experiment
  2. jcsd
  3. Aug 30, 2006 #2


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    Mmh the law is "you have to exert a constant force of kx to maintain the spring stretched a distance x from its position of equilibrium", where k is the spring constant. But ultimately, you have to find k experimentally.
  4. Aug 30, 2006 #3
    quasar987 is correct; k can only be determined experimetally. Once you have that:

    A simple form of Hooke's law
    F = force. k = spring constant. x = displacement from relaxed (not stretched or compressed). Note the right side is negative to denote "equal but opposite".

    [tex]PE = \frac{1}{2}kx^2[/tex].
  5. Aug 31, 2006 #4

    Doc Al

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    The negative sign in Hooke's law indicates that the direction of the restoring force is opposite to the displacement from the unstretched position. For example: Displace the end of the spring to the right, the spring force acts to the left.
  6. Aug 31, 2006 #5


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    ...if you don't have K, though, you can still calculate it from the properties of the material and shape of the spring.
  7. Aug 31, 2006 #6
    thx, that helped a lot
  8. Sep 1, 2006 #7


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