| A | B |
|---|
| Work | use of force to move an object some distance in the direction of the force |
| Energy | ability to do work |
| Newton-meter | unit of measure for work; also called a Joule |
| Joule | metric unit of measure for work; also known as a newton-meter |
| Watt | metric unit of measure for power |
| Kinetic energy | energy of an object due to motion |
| Potential energy | energy of an object due to its position, condition, or chemical composition |
| Mechanical energy | energy possessed by an object due to its motion and position; potential and kinetic energy combined |
| Gravitational potential energy | potential energy caused by an objects position above the ground |
| Mechanical potential energy | potential energy that depends on an object's position |
| Chemical potential energy | potential energy caused by the arrangement of chemical bonds between atoms |
| Elastic potential energy | potential energy that is due to an object being stretched or compressed |
| Machine | any device that helps people do work by changing the way work is done |
| Mechanical advantage | number of times the machines multiplies the input force |
| Mechanical efficiency | comparison of a machine's work output with the work input |
| Lever | simple machine that has a bar that pivots at a fixed point |
| Fulcrum | fixed point of a lever |
| Wheel and axle | simple machine that is made of a wheel connected to an axle |
| Pulley | simple machine that has a grooved wheel that holds a rope or cable |
| Inclined plane | simple machine that is a straight, slanted surface |
| Input force | force applied to a machine through a distane |
| Output force | force a machine exerts on an object |
| Work input | work you do on a machine |
| Work output | work done by the machine on a object |
| Ideal mechanical advantage | mechanical advantage of a simple machine that does not take friction into account |
| First-class lever | lever where the fulcrum is between the load and the input force; example a seesaw |
| Second-class lever | lever where the load is inbetween the fulcrum and the input force; example a wheel barrow |
| Third-class lever | lever where the input force is inbetween the fulcrum and the load; example a baseball bat |
| Fixed pulley | pulley that is attached to something that does not move; example pulley at the top of a flag pole |
| Movable pulley | pulley that is attached to the object being moved |
| Block and tackle pulley | pulley that is a system of pullies made by combining a fixed and a movable pulley |
| Wedge | simple machine that is a pair of inclined planes that move and are used to pierce or cut |
| Screw | simple machine that is an inclined plane wrapped around a central point |
