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Homework Help: Cannon Question

  1. Jul 7, 2009 #1
    1. The problem statement, all variables and given/known data
    A cannon of mass 5.80 x 10^3 kg is rigidly bolted to the earth so it can recoil only by a negligible amount. The cannon fires an 85.0-kg shell horizontally with an initial velocity of +551 m/s. Suppose the cannon is then unbolted from the earth and no external force hinders its recoil. What would be the velocity of a shell fired by this loose cannon? (Hint: In both cases assume that the burning gunpowder imparts the same kinetic energy to the system.)

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Jul 7, 2009 #2


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    Homework Helper

    Two conservation laws apply here. One of them is already implicitly mentioned in the hint. The other one has to do with the masses and velocities.
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