What scientific principle keeps coming up . . . and up . . . when designing Disney's theme park attractions? Trajectory! The Imagineers demonstrate how forces and motion play a leading role in creating rides like Disney California Adventure's California Screamin' and Toy Story Midway Mania. Learn the definitions of ''projectile'' and ''trajectory,'' see how Newton's First Law of Motion relates to these principles, and how to apply the physics of motion to predict and control the trajectory of a projectile.