No one said energy was conserved!!!!
Momentum is conserved in the x direction
AND
Momentum is conserved in the y direction
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!!
2 answers
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
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
2 answers