(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A small 10.0-g bug stands at one end of a thin uniform bar that is initially at rest on a smooth horizontal table. The other end of the bar pivots about a nail driven into the table and can rotate freely, without friction. The bar has mass 60.0g and is 90cm in length. The bug jumps off in the horizontal direction, perpendicular to the bar, with a speed of 25.0cm/s relative to the table.

2. Relevant equations

L = Iw

P = mv

3. The attempt at a solution

I calculated the linear momentum of the bug: p=0.01(.25) = 0.0025

I then set that equal to the momentum of the rod: 0.0025 = Iw. The moment of inertia for the rod is I=(1/3)MR^2. Therefore I = (1/3)(0.06)(0.9)^2 = 0.0162.

0.0025 = (0.0162)w. Solve for w. I get w = 0.154 rad/s. I have tried both positive and negative values for w and neither are correct. What am I doing wrong? This is for Mastering Physics, so the values are a little bit different from the textbook. However, when I plugged in textbook values, I get the same answer as the answer in the back of the book, so my method doesn't seem to be wrong...

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# Homework Help: Simple bug on uniform rod rotational momentum problem

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