(101)Conservation of linear momentum

AI Thread Summary
The discussion centers on a physics problem involving the conservation of linear momentum, where a man throws a book while standing on a frictionless ice surface. The initial calculation for the momentum of the book is correct at 1.12 kg·m/s, leading to the equation 1.12 = 86.7v for the man's velocity. The user initially calculated the man's speed as 0.0723 m/s but later realized a mistake in their calculator use, resulting in confusion about the correct answer. The final correct calculation shows that the man's speed should be approximately 0.0129 m/s. The conversation highlights the importance of careful calculation and understanding of momentum conservation principles.
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[SOLVED] (101)Conservation of linear momentum

Homework Statement


A 86.7 kg man is standing on a frictionless ice surface when he throws a 0.1 kg book at 11.2 m/s. With what speed does the man move across the ice as a result?


Homework Equations


Since the momentum of the thrown book must equal that of the man in the opposite direction, m1v1=m2v2, or so I thought.


The Attempt at a Solution



I solved for the momentum of the book (.1)(11.2)=1.12 and then set that equal to the man*v

So... 1.12=86.7v, v=.0723

But that's was incorrect. So, no credit on my webassign homework but I would still like to understand how to solve it. Can someone help me out?
 
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When I divide 1.12 by 86.7, I get 0.01291811 ;-)
 
UGH! you're completely right... I mustve just been to antsy with the ANS key on my calculator... how irritating. But my reasoning is sound I assume?
 

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