00:01
Okay, so in this problem, we have our cue ball that is striking another ball, and we know the angle that the cue ball makes with its original velocity trajectory, which i've drawn here in the x direction, and this angle is 22 degrees, and we know the final velocities of the two balls.
00:20
The final velocity of the cue ball is 3 .50 meters per second.
00:23
Final velocity of the other ball is 2 .00 meters per second.
00:28
So to start, we need to figure out what the angle theta 2 is, the angle that the second ball makes with the original trajectory.
00:39
And to do that, we can analyze the perpendicular components, the y components of these two speeds and these two velocities.
00:48
So the original q ball, the way that i have it drawn here, has no momentum in the y direction.
00:56
So the two momentums need to be the same.
01:00
So the mass of the cube ball times its final velocity, which i labeled the vc, times the sign of theta 1, minus the mass of the ball times its velocity, which i labeled b, times sine of theta 2.
01:22
So this has to be true...