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

Consider an elastic collision (ignoring friction and rotational motion). A queue ball initially moving at 2.9 m/s strikes a stationary eight ball of the same size and mass. After the collision, the queue ball’s final speed is 1 m/s. Find the queue ball’s angle with respect to its original line of motion.

Answer in units of ◦.

2. Relevant equations

I can't seem to figure out how you're supposed to get an angle for this, if none is given.

3. The attempt at a solution

in 1-d the equation would be something like m1v1+m2v2=(m1+m2)*V. In 2-d, I assume you need a trig function, but how is that useful with no given angle?

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# Elastic collision in 2-d.

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