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Homework Help: Simple spring constant problem

  1. Oct 20, 2006 #1
    The length of a spring increases by 6.90 cm from its relaxed length when a mass of 1.10 kg is suspended from the spring.What is the spring constant?

    so I know that ultimately i use hooke's law which is
    but how would i figure out F if i only have the mass?

    I can't do F=ma b/c i don't have the acceleration.
    I'm confused
  2. jcsd
  3. Oct 20, 2006 #2


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    Note that this spring will be vertical when the mass is suspended from it.
  4. Oct 20, 2006 #3
    so will i assume that the force is the mass of the spring.
    (1.10) = k (6.90)

    but it says i'm wrong
  5. Oct 20, 2006 #4


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    The force can't equal the mass. Weight can be a force, and it equals m*g.
  6. Oct 20, 2006 #5
    i think i wasn't thinking straight :)
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