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Homework Help: Problem of Springs

  1. Dec 8, 2003 #1
    A particle has displacment given by[tex]x=3.0\cos(5\pi t+\pi)[/tex] where x is in meters and t in seconds

    A)What are the frequency ,F, and the period,T, of motion
    B)What is the greatest distance the particle travels from equlibrium
    c)Where is the particle at time t=0?t=0.5(s)
    D)What is the velocity when t=0.5s

    A)F=2.5, T=0.4
    B)3.0M
    c)3.0M
    d)no idea

    thank you
     
  2. jcsd
  3. Dec 8, 2003 #2
    Apply the formula for velocity i.e dy/dx
     
  4. Dec 8, 2003 #3
    I have no idea what you are talking about? are my other answers correct?
     
  5. Dec 8, 2003 #4
    Others are correct i thought you need to calculate the velocity
    dont u
     
  6. Dec 8, 2003 #5
    yes i need to calculuate velocity, but i dont know how to get it.
     
  7. Dec 8, 2003 #6
    Look you got the displacement, Pls tell yourself what is the relation between displacement and velocity
     
  8. Dec 8, 2003 #7
    ok so i have to take the derivative

    [tex]x=3.0\cos(5\pi t+\pi)[/tex]

    so the derivative of that would be

    [tex]3.0*-\sin(5\pi(0.5)+\pi)*d/dx(5\pi(0.5)+\pi[/tex]
     
  9. Dec 8, 2003 #8
    Yes You got it right
     
  10. Dec 8, 2003 #9
    yes but i get v=0 when i do the derivative. is this correct?

    thnx for ur help
     
  11. Dec 8, 2003 #10
    Sorry U didn't write correctly
    it should be
    [tex]3.0*-\sin(5\pi(0.5)+\pi)*d/dt(5\pi(0.5)t+\pi[/tex]

    I want to correct myself
    the velocity is time derivative
    i.e v = dx/dt.

    i just wanted to point towards the calculus involved
     
  12. Dec 8, 2003 #11
    thnx a lot man
     
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