Cannon at rest shot on frozen pond. what is cannon balls v after cannon recoil?

AI Thread Summary
The discussion centers on a physics problem involving a cannon on a frozen pond, where a 253.5 kg cannon fires a 6.8 kg cannonball horizontally, resulting in the cannon recoiling at 6.9 m/s. The conservation of momentum principle is applied to determine the cannonball's velocity after firing. Calculating the momentum before and after the shot, the equation 253.5 kg * 6.9 m/s = 6.8 kg * velocity of cannonball is used. The resulting calculation suggests the cannonball's velocity is -257.22 m/s, indicating it moves in the opposite direction to the cannon's recoil. The discussion highlights the importance of understanding momentum conservation in such scenarios.
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A 253.5 kg cannon rests on a frozen pond. The cannon is loaded with a 6.8 kg cannon ball and is fired horizontally. If the cannon recoils to the right with a velocity of 6.9 m/sec , then what is the velocity (in m/s) of the cannonball just after it leaves the cannon?

Also would like a hint to start it! thanks
 
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momentum is conserved
momentum is mass * velocity
 
253.5*6.9=1749.15/6.8=-257.22

i think the answer should be negative or so I am told?
 
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