A boy pulls his 9.0 kg sled, applying a horizontal force of 14.0 N (rightward). The coefficient of friction between the snow and the sled is 0.12. Determine the net force and the acceleration of the sled. Draw a free-body diagram for the sled; use appropriate force symbols to label the type of each force acting on the sled.

In a game of pool, ball a is moving with a velocity v0 of magnitude v0 = 15 ft/s when it strikes balls b and c, which are at rest and aligned as shown. knowing that after the collision the three balls move in the directions indicated and assuming frictionless surfaces and perfectly elastic impact (that is, conservation of energy), determine the magnitudes of the velocities va, vb, and vc.