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**[SOLVED] Final Velocity (involving momentum)**

**1. Homework Statement**

A 0.329-kg puck, initially at rest on a frictionless horizontal surface, is struck by a 0.222-kg puck that is intitially moving along the x-axis with a velocity of 2.24 m/s. After the collision, the 0.222-kg puck has a speed of 1.24 m/s at an angle of 24 degrees to the positive x-axis. (a) Determine the velocity of the 0.329-kg puck after the collision. (b) Find the fraction of the kinetic energy lost in the collision.

**3. The Attempt at a Solution**

i tried m1 = 0.329kg ----- m2 = 0.222kg

m1v1(i) + m2v2(i) = m1v1(f) + m2v2(f)

v1(f) = [m2v2(i) - m2v2(f) cos theta] / m1

v1(f) = 0.7471105 m/s (this was wrong)

I assume I need to find the x and y components and then use vector sumation but I have NO idea how to find the y...