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Homework Help: Help on Ballistic Pendulum Angle

  1. Oct 14, 2008 #1
    1. The problem statement, all variables and given/known data

    A bullet (m = 0.029kg) is fired with a speed of 95.00m/s and hits a block (M = 2.40kg) supported by two light strings , stopping quickly. Find the height to which the block rises.

    The correct answer is 6.56E-02 m

    BUt the next question is:

    Find the angle (in degrees) through which the block rises, if the strings are 0.50 m in length.

    i dont know how i get that angle... could anyone help plz?....
  2. jcsd
  3. Oct 14, 2008 #2
    I think if you draw a free-body diagram and break each string into x and y components. you could use trig.

    Sorry, don't know now exactly if this helps, but maybe it will.
  4. Oct 14, 2008 #3
    nop... it doesnt function because the trangle formed isnot a rectangle one...
  5. Oct 14, 2008 #4
    anyone know how to find that angle?....
  6. Oct 14, 2008 #5
    yes i got it....

    L - L cos(angle)= h

    then we get:
    angle = inverse cos ((L - h)/L )

    for this exersice the correct answer is 29.68
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