(101)Conservation of linear momentum

[WPCareyDevil]

[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?

 

[cepheid]

When I divide 1.12 by 86.7, I get 0.01291811 ;-)

 

[WPCareyDevil]

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?