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

The drawing shows a collision between two pucks on an air-hockey table. Puck A has a mass of 0.0180 kg and is moving along the x axis with a velocity of +7.71 m/s. It makes a collision with puck B, which has a mass of 0.0360 kg and is initially at rest. The collision is not head-on. After the collision, the two pucks fly apart with the angles shown in the drawing. Find the speed of (a) puck A and (b) puck B.

http://edugen.wileyplus.com/edugen/courses/crs2216/art/qb/qu/c07/ch07p_30.gif

**2. Relevant equations**

m

_{1}v

_{f1x}+m

_{2}v

_{f2x}= m

_{1}v

_{o1}+m

_{2}v

_{o2}

0 = M

_{f1}V

_{1}sin(65) - M

_{2}V

_{f2}sin(37)

M

_{1}= .0180

M

_{2}= .0360

V

_{o1}= 7.71

V

_{o0}= 0

**3. The attempt at a solution**

.018(v)+.036(v) = .018(7.71)

.054v = .13878

v = 2.57. (Terribly wrong)

.018(V

_{f1})sin(65) - .036(V

_{f2})sin(37)

My problem is I'm getting so confused as to what I am solving for. I mean, I know I'm solving for the final speeds of puck A and puck B but I'm confused as to how to get there. I'm just plan lost.