Some useful terms
Acceleration: The rate at which an object changes its velocity.An object is accelerating
if it is changing its velocity, both speeding up and slowing down.
Centripetal force requirement: inward force acting upon an object that is moving in a
circle, in order to cause its inward acceleration.
Energy: “Nature’s way of keeping score.” Measured in joules.Appears in many forms,
most of which are ultimately derived from the sun or from radioactivity.
Force:Apush or pull. The force applied to a machine is called work input or effort force.
Gravitational Potential Energy: Potential energy due to elevated position. Gravitation
potential energy = weight x height. Note this only depends on vertical displacement and
not the path taken to get it there. This value is always relative to some reference level.
Inertia: The tendency of matter to remain at rest if at rest, or, if moving, to keep moving
in the same direction, unless affected by an outside (or unbalanced) force.
Kinetic Energy (KE): Energy of motion. KE= ½ mass x velocity = ½mv Note that
small changes in speed can result in large changes of KE (it’s speed squared!). Net force
x distance = KE. Includes heat, sound, and light (motion of molecul