| A | B |
|---|
| Machine | a device that makes work easier |
| simple machine | does work with only one movement |
| effort force | force applied to the machine |
| resistance force | force applied by the machine |
| work input | work done on the machine |
| work output | work done by the machine |
| ideal machine | work input = work output |
| formula for work | Force x Distance |
| work output is always ______ than work input | smaller |
| mechanical advantage | the number of times a machine multiplies the effort force |
| Formula for MA | Resistance force divided by effort force |
| Some machines don't multiply force, they only change_____ | direction |
| example of a simple machine | screwdriver |
| example of a compound machine | bicycle |
| lever | bar that is free to pivot about a fixed point |
| fulcrum | the fixed point of a lever |
| effort arm | part of a lever where effort force is applied |
| resistance arm | part of a lever that exerts resistance force |
| Types of levers | first class, second class, third class |
| Your foot is an example of a ______ class lever | second |
| your head on your neck is an example of a _____ class lever | first |
| your elbow is the fulcrum of a _____ class lever | third |
| pulley | grooved wheel with a rope |
| fixed pulley | changes direction of an effort force |
| movable pulley | multiplies the effort force |
| Ideal MA of a fixed pulley | 1 |
| Ideal MA of a movable pulley | 2 |
| block and tackle | a combination of fixed and movable pulleys |
| to find the MA of a pulley | count the ropes supplying an upward force |
| IMA of a wheel and axle | radius of wheel divided by the radius of the axle |
| a screw is _______ | an inclined plane wrapped around a cylindrical post |
| wedge | inclined plane with one or two sloping sides |
| efficiency | a measure of how much work input is changed to work output |
| formula for efficiency | work output divided by work input x 100% |
| power | the rate at which work is done |
| formula for power | work divided by time |
