After a completely inelastic collision, two objects of the same mass and initial speed are found to move away together at 1/2 their initial speed. Find the angle between the initial velocities of the objects.(adsbygoogle = window.adsbygoogle || []).push({});

Solution is here http://www.physics.sfsu.edu/~senglish/APphysicswebsite/collisions/solutions%20on%20collisions/17.pdf [Broken]

My first atempt to solve this problem was drawing my diagram so that both objects converge towards the positive y-axis instead of the positive x-axis as seen in solution.

v=initial velocity vf= final velocity

so the x-comp mv cos A - mv cos B= 0

y-comp mv sin A + mv sin A = 2m vf

Well it didn't work, so i gave up and redrew my diagram like the one in the solution and solved it that way. I'm starting to conclude that my original idea solved for a different angle for the problem.

What did i do wrong in solving the problem with my original diagram with the objects converging towards the positive y-axis

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# Homework Help: Need help on Collision problem

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