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Homework Help: Spring help please

  1. Apr 12, 2004 #1
    I am doing some revision for physics and cant evaluate these questions, can anybody help or give a formula.


    A mass of 2.2 Kg is suspended from a spring of spring constant K = 25 Nm^-1
    What is the initial extension?


    The mass (in Q1) is pulled down a further 5cm and released.
    What is the initial upward acceleration?


    Calaculate the velocity of the mass as it passes through the equilibrium position.


    What is the value of period?

    Thanks so much :-)
  2. jcsd
  3. Apr 12, 2004 #2
    Have you tried solving any of these questions yourself?
  4. Apr 12, 2004 #3
    Im new to physics but yes i have tried
  5. Apr 12, 2004 #4
    What have you tried using? :smile: At least the first question is very simple, but if you are not able to understand it or answer it, how do you expect to understand the other questions? I am not trying to put you down or anything. It's for your own good, really.

    "Give a man a fish; you have fed him for today. Teach a man to fish; and you can sell him fishing equipment."
  6. Apr 12, 2004 #5
    force= k*x
    Initial extension is 0.784m
    work=force*distance cos angle
    since the force and the displacement are in the same direction, then
    work of spring=0.5*k*x^2-0.5kx^2
    work due to gravity is mgh-mgh=0-2*9.8*(.784+.05)=16.3joule
    total work= 10.425+16.3=26.7joule
    work=change in kinetic energy=.5(mV^2-mV^2)=.5(2V^2-0)
    period= 1/frequency
    frequency=number of cycles/time
    the number of cycles is not give in the example
    i think it is supposed to be in the example
    anyway i hope that this solution would be correct as i beleive.....actually think so
    best wishes

    Yes i have noticed that i used the mass value as 2 instead of 2.2 sorry
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