How Do You Calculate the Final Velocities in a 2D Coin Collision Problem?

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AI Thread Summary
To calculate the final velocities in a 2D coin collision problem, the initial conditions include one coin at rest and the other moving towards it. The equations of motion involve conservation of momentum in both x and y directions, as well as conservation of kinetic energy. The user is attempting to solve for the final velocities but is struggling with the calculations, particularly in determining the initial velocity of the moving coin before the collision. They suspect that the acceleration due to friction might play a role in finding the final velocity after the collision. Clarification on how to apply the equations effectively is sought to resolve the calculations.
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Homework Statement



Two coins, one at rest (c1), the other flicked towards the other (c2). Initial positions are marked, as are final positions and angles. Coordinate system's origin is placed at center of C1 with +x in direction of C2's motion.
knowns:
\mu = .36
V1 = 0
C1 final position- 10.25 cm @ 16 degrees
C2 final position- 5.6 cm @ 302 degrees (-58 degrees)
m1 = m2

UNKNOWNS-
V2
V1F
V2F

Homework Equations



(x):
m2v2 = m1fv1fcos(16) + m2fv2fcos(302)

(y)
0 = m1fv1fsin(16) + m2fv2fsin(302)

(cons. of KE)

1/2m1v12 + 1/2m2v22 = 1/2m1fv1f2 + m2fv2f2

(acceleration? idk if this is necessary...)

a = \mug
-- derived from \SigmaF = ma = \mumg... not sure if there should be any other forces in this...

The Attempt at a Solution



i keep getting .36587vf2 = 2.0767vf2

i have a feeling i need to find v2 right before collision using v2 = vo2 + 2a(x-xo)
 
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with a = \mug but i have no idea how to use that equation to solve for v2 after the collision (v2f)any help is appreciated :)
 
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