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Homework Help: Impulse Q

  1. Oct 1, 2006 #1
    A cue exerts an average force of 7N on a stationary snooker ball of mass 200g if the impact lasts for 45ms, with what speed does the ball leave the que?

    ---

    Ft = mv - mu
    F = m(v-u/t)
    F = 0.2(v-0/0.0045)
    = 0.2v/0.0045 = 44.4444V

    Can't figure out what the next step is from my notes.

    Cheers
     
  2. jcsd
  3. Oct 1, 2006 #2

    radou

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    Homework Helper

    Simply stated, the impulse equals the change of linear momentum, so, you have: [tex]F\cdot t = mv_{2}-mv_{1}[/tex], where m is the mass of the ball, v2 the final velocity and v1 the initial velocity (equals zero). From this equation you can easily retrieve v2.
     
  4. Oct 2, 2006 #3
    I already did that.
     
  5. Oct 2, 2006 #4

    radou

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    I saw you did that and I don't see where the problem is. Just plug in the force and solve to get the speed v.
     
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