Two balls have the same mass. One ball moving along the positive x–axis and the other ball moving along the positive y–axis undergo perfectly inelastic collision. What can you say about the motion of the balls after the collision? A.
The balls stick and move together.
B.
The balls separate immediately.
C.
The first ball stops while the other ball starts moving.
D.
The two balls travel off in opposite directions, 180° apart.

Asled is being held at rest on a slope that makes an angle θ with the horizontal. after the sled is released, it slidesa distance d1 down the slope and then covers the distance d2 alongthe horizontal terrain before stopping. find the coefficient ofkinetic friction μk between the sled and the ground, assumingthat it is constant throughout the trip. find the coefficient of kinetic frictionμk. express your answer in terms of someor all of the variables d1, d2, and θ.