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Doc Al
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Jul15-10, 07:11 AM
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Quote Quote by metalrose View Post
The question I want to ask is, how can the momentum be conserved, when there IS a net external force on the syetm of (acrobat + monkey)? The net external force is (M + m)g downwards, so can we apply the conservation of linear momentum?
You're only applying conservation of momentum during the brief time that he grabs the monkey: just before versus just after. Too brief a time to worry about gravity. For longer times--like as they rise together after the grab--you know that momentum is not conserved.