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Homework Help: Help with a Simple Harmonic Motion problem!

  1. Nov 18, 2007 #1
    1. A 25.0g bullet strikes a .600kg block attached to a fixed horizontal spring whose spring constant is 6.70x10^3 and sets it into vibration with an amplitude of 21.5cm. What is the speed of the bullet before impact if the two objects move together after impact?

    2. V=A[tex]\sqrt{k/m}[/tex]

    3. I used the equation above, adding the masses together (.625kg). I got the velocity to be 22.26m/s... but now i can't figure out how to get the speed of the bullet.

    The answer in the book says that the speed of the bullet is 557m/s.
    Last edited: Nov 18, 2007
  2. jcsd
  3. Nov 18, 2007 #2


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    Use conservation of momentum. momentum of the bullet before the impact = momentum of the block plus bullet moving together at 22.26 m/s
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