(adsbygoogle = window.adsbygoogle || []).push({}); 1. In Fig. 10-41, ball 1 with an initial speed of 12 m/s collides elastically with stationary balls 2 and 3 that are initially in contact with each other. The centers of balls 2 and 3 are on a line perpendicular to the initial velocity of ball 1. The three balls are identical. Ball 1 is aimed directly at the contact point, and all motion is frictionless.(Hint: With friction absent, each impulse is directed along the line connecting the centers of the colliding balls, normal to the colliding surfaces.)

2. momentum = mv, KE = 1/2mv2

3. after the collision, marbles two and three are going at the same velocity and angle; lets call them vcos(x). marble 1 is going in the opposite direction it had been traveling at initially. so since v2 = v3 , my final equations are 12 = 2v2cos(x) - v1 (mass cancels out). since there are two unknowns, i wrote a second equation: 1/2(12)^2 = v1^2 + 1/2(v2cos(x))^2, tried to solve using substitution, and didnt work. For angle x, i've tried both 30 degrees and 45 degrees. I did this using various methods about ten times. help :(

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# Homework Help: Collision/conservation of momentum & energy

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