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Homework Help: Calc/Trig Hybrid

  1. Jan 15, 2008 #1
    1. The problem statement, all variables and given/known data

    A mass is suspended from the ceiling on a spring. It is pulled down to point P and then released. It oscillates up and down. Its distance, s cm, from the ceiling, is modeled by the function s=48 + 10cos([tex]\Pi[/tex]t) where t is the time in seconds from release.

    (a)What is the distance of the point P from the ceiling. Do not use a calculator

    (b) Find ds/dt

    2. Relevant equations

    The Unit Circle

    3. The attempt at a solution

    (a) I set it equal to zero, and then used the unit circle to find that cos([tex]\Pi[/tex]) = 1, but that doesn't take into account the t.
  2. jcsd
  3. Jan 16, 2008 #2


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    The "point of initial release" is where t=0 isn't it? Besides cos(pi)=(-1).

    Signed, Confused.
    Last edited: Jan 16, 2008
  4. Jan 16, 2008 #3
    Oh, you're right about cos(pi)=(-1)
  5. Jan 16, 2008 #4


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    He's also right about the mass being at point P when t= 0!
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