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JessGold
Jul7-09, 12:27 PM
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

CompuChip
Jul7-09, 01:05 PM
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.