Discuss the universality of the force of gravity. Introduce Newton's observations regarding inertia, constant motion, straight line motion, constant velocity and forces. Review that a force is required to cause acceleration. Discuss why the moon's movement and an apple falling are examples of acceleration. Elicit that the force causing the acceleration is gravity. Sketch and discuss the paths of a cannonball fired from a very high point on the Earth. Show that eventually, given sufficient velocity, the cannonball would orbit the Earth and land. Discuss tangential velocity and elicit a definition for gravity.