vocab

2. a type of lever that is a wheel with a groove in its rim, and one that is used to change the direction of a force
5. the SI unit of work and of all other forms of energy; one joule (J) of work is done when a force of one newton (N) is exerted on an object moved one meter (m) in the direction of the force
9. energy of motion, equal to half the mass multiplied by the speed squared
10. the ratio of useful energy output to total energy input, or the percentage of the work input that is converted to work output
13. the ratio of output force to input force for a machine
14. the pivot point of a lever

1. energy cannot be created or destroyed; it may be transformed from one form into another, but the total amount of energy never changes
2. energy of position, usually related to the relative position of two things, such as a stone and the earth
3. the product of the force on an object and the distance through which the object is moved
4. the energy due to the position or the movement of something; potential or kinetic energy (or a combination of both)
6. a simple machine, made of a bar that turns about a fixed point
7. rate at which work is done or energy is transformed, equal to the work done or energy transformed divided by time
8. a device for increasing (or decreasing) a force or simply changing the direction of a force
11. that property of an object or a system which enables it to do work
12. the SI unit of power; one watt (W) is expended when one joule (J) of work is done in one second (s)