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Homework Help: How do u find the height of an object thrown straight up

  1. Mar 27, 2006 #1
    how do u find the height of an object thrown straight up if u are only given that it is thrown with a velocity of 30m/s
     
  2. jcsd
  3. Mar 27, 2006 #2

    arildno

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    Energy conservation..
     
  4. Mar 27, 2006 #3
    so how do i do it
     
  5. Mar 27, 2006 #4

    arildno

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    Write down the equation for energy conservation, perhaps?
     
  6. Mar 27, 2006 #5
    how exactly is the question worded?
     
  7. Mar 27, 2006 #6

    daniel_i_l

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    What is the initial kinetic energy? If that energy is turned to potential energy, how high is the object?
     
  8. Mar 27, 2006 #7
    because energy is conserved, all the kinetic energy will be converted to potential energy
    KE = PE
    1/2 mv^2 = mgh
    1/2 v^2 = gh
    1/2 (30)^2 = 9.8 h
     
  9. Mar 27, 2006 #8

    arildno

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    ThomasW:
    Let the original poster try to solve the problem on her own before providing a full solution.

    Welcome to PF, by the way.
     
  10. Mar 27, 2006 #9
    alrite, arildno
    i'll do that from now on
     
  11. Mar 28, 2006 #10
    u can also use equations of motion
    ie is v^2=u^2+2gs
    where v is final velocity here it is 0,
    where u is initial velocity(given)
    where g is acceleration due to gravity
    where s is the distance or height reached.
     
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