# A particle of mass m1 = 2.5 kg moving along the x axis collides with a particle of mass m2 = 4.9 kg initially at rest. The incoming particle is deflected in the direction 22 degrees above the x axis, whereas the target particle moves off at 15 m/s at 37 degrees below the x axis. What are the initial and final speeds of the 2.5 kg particle?

I've tried this question at least 4 different ways and no matter what I do, I keep getting the same wrong answer. The last thing I did was a system of equations using the conservation of momentum equation, ΔP = P1 = P2, and the conservation of kinetic energy, ΔK = K1 = K2.

Also please hurry this is due tonight!!

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1. No one said energy was conserved!!!!

Momentum is conserved in the x direction
AND
Momentum is conserved in the y direction

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2. Initial x momentum = 2.5 u
Initial y momentum = 0

Final x momentum = 2.5 V cos 22 + 4.9 (15) cos 37

Final y momentum = 2.5 V sin 22 - 4.9(15)sin 37

SO

use final y momentum = 0 to get velocity of particle 2

4.9(15) sin 37 = 2.5 V sin 22

then go back and use the x momentum to get u, the initial speed

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