I don't understand how to do equilibrium problems. I don't know how to set them up and where to start. here is an example. Can anyone please help?(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

A uniform thin rod of length 0.50m and mass 4.0 kg can rotate in a horizontal plane about a vertical axis through its center. The rod is at rest when a 3.0g bullet traveling in the rotation plane is fired into one end of the bullet's path makes angle = 60.0 degrees with the rod. If the bullet lodges into the and the angular velocity of the rod is 10 rad/s immediately after the collision, what is the bullet's speed just before impact.

2. Relevant equations

1/2mv^2=1/2Iw^2

I=1/12ML^2

3. The attempt at a solution

K-initial=K-final

1/2mv^2=1/2Iw^2

solve for v>>>>

v=sq. root[Iw^2/m]

v=sq. root[(1/12*ML^2)w^2/m]

v=sq.root.[(1/12*4.003*.50^2)*10^2/.003]

v=52.7m/s

The answer is 1.3*10^3m/s.

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# Homework Help: Can someone help me with Equilibirum?

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