Work and Machines Vocabulary
1. Work- force exerted on an object that causes it to move
2. Joule- a unit of work equal to one newton per meter
3. Power- the rate at which work is done
4. Machine-a device that changes the amount of force exerted, the distance over which a force is
exerted, or the direction in which force is exerted.
5. Input force- the force exerted on a machine
6. Output force- the force exerted on an object by a machine
7. Input work- the work done on a machine as the input force acts through the input distance
8. Output work—the work done by a machine as the output force act through the output distance
9. Mechanical advantage- the number of times a machine increases a force exerted on it.
10. Efficiency – the percentage of the input work that is covered to output work
11. Inclined plane- a simple machine that is a flat, sloped surface
12. Wedge- a simple machine that is an inclined plane that moves
13. Screw- a simple machine that is an inclined plane wrapped around a central cylinder to form a
spiral
14. Level- a simple machine that consists of a rigid bar that pivots about a fixed point
15. Fulcrum- the fixed point around which a level pivots
16. Wheel and axle- a simple machine that consists of two attached circular or cylindrical objects
that rotates around a common axis, each one with a different radius
17. Pulley – a simple machine that consists of a grooved wheel with a rope or cable wrapped
around it.
18. Compound machine-a device that combines two or more simple machines.