An aircraft in level flight is travelling due east at a constant speed when it is acted on by a horizontal wind force of 800n.
resolve the wind force into two perpendicular components and determine the component of the wind force along the line in which the aircraft is moving.

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.