physics
posted by Kyle on .
Two 72.0kg hockey players skating at 7.00 m/s collide and stick together. If the angle between their initial directions was 130 degrees , what is their speed after the collision?

Use conservation of momentum in two perpendicular directions. Because of the equal speeds, the final direction will bisect the angle between the incoming vectors. You can write a single momentum equation along that direction, and solve for final speed Vfinal
2*72 * cos 65*7.00 m/s= 2*72 * Vfinal
Vfinal = 7.0 cos 65