Finding Velocity given the initial velocity and weight

AI Thread Summary
To find the velocity of the raft after the man jumps, conservation of momentum should be applied. The initial momentum of the system (man and raft) is equal to the final momentum after the jump. The initial momentum can be calculated using the man's mass and initial velocity, while the final momentum will include the man's velocity after the jump and the raft's velocity. The discussion highlights the confusion regarding which variables to use, emphasizing the importance of understanding momentum conservation in solving the problem. Ultimately, applying these principles will yield the raft's velocity post-jump.
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Homework Statement


An 80-kilogram man jumps off a raft that weighs 100 kg. His initial velocity from jumping is 7 meters per second. Assuming that the friction resistance of the water is zero, the velocity of the raft after the man jumps will be?


Homework Equations


Vf^2= Vi^2 + 2aD

The Attempt at a Solution


I am trying to figure out the velocity of that raft after the man jumps, the question is confusing me on which variable I need to solve the problem. Any help?
 
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