I've been stuck on this questions for 2 days

A 7.2-kg bowling ball traveling at a speed of 3.5 m/s collides with a 1.2-kg bowling pin at rest. After the collision, the pin moves with a speed of 3.0 m/s at an angle of 60° with respect to the original direction of motion of the bowling ball. What is the final velocity of the ball (magnitude and direction)? Is the collision approximately elastic?

1 answer

momentum is conserved in both the x and y directions

the initial momentum is all in the x direction -- the moving ball

PMy = 3.0 m/s * sin(60º) * 1.2 kg

BVy = PMy / 7.2

PMx = 3.0 m/s * cos(60º) * 1.2 kg

BVx = 3.5 - (PMx / 7.2)

use Pythagoras to find BV