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Homework Help: Collision Questions

  1. Oct 9, 2012 #1
    1. Jamie and Adam fire a cannon with a mass of 1150 kg. As the 14.5 kg cannonball leaves the cannon, the cannon recoils with a velocity of 1.75 m/s. How fast does the cannonball fly?

    2. A 45 kg cart rolls along a railroad track at 4.0 m/s. A dog running at 7.6 m/s to catch up with the cart jumps on the cart. After the dog jumps on the cart, the cart is moving at 6.0 m/s. What is the mass of the dog?




    2. m1v1 + m2v2 = (m1+m2)Vf

    m1v1 + m2v2 = m1v1 + m2v2

    (m1 + m2)*Vi = m1v1 + m2v2




    3. I'm not sure what equation to use...
     
  2. jcsd
  3. Oct 9, 2012 #2

    SammyS

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    Do you know what principle those equations are based on ?
     
  4. Oct 9, 2012 #3
    Collision? I'm sorry, I'm not exactly sure what you're asking.
     
  5. Oct 10, 2012 #4

    SammyS

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    They're based on conservation of something .

    Do you know what that something is?
     
    Last edited by a moderator: Oct 10, 2012
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