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

"A bar line AB has a length of 1,5m and a mass of 0,5kg.

It is stuck in the point B in a horizontal fixed hub, and it can oscillate freely with no friction in the verical plane.

at time t=0, the bar line, which was still (not moving, inertia), is set free to rotate.

When it reaches the vertical position it hits a body of mass m2 = 0,2kg.

The bar line immediately stops, while the body m2 begins to move after the collision with a horizontal velocity.

Find: The angular velocity of the bar line, the linear velocity of its free extreme point (so A, i guess), and the velocity of m2 after the collision.

2. Relevant equations

We have then:

AB = 1,5m

m1 = 0,5kg

m2 = 0,2kg

v0 = 0m/s

3. The attempt at a solution

Alright, I didn't do too much actually, I am just starting out with these kind of problems.

I understand that as soon as the bar line is set free, it starts a circular motion, and the final velocity depends on the gravity acceleration ( I guess ). And that the impact will be at angle teta = pi/2.

Now, I don't really know where to start from.

I am thinking about finding the center of mass, is that the right path to begin with?

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# Homework Help: Collision with an object after circular motion.

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