This is a draft cheat sheet. It is a work in progress and is not finished yet.
Work
Work |
Force x Distance |
Do all forces do work? |
Only parellel forces do work |
Force Distance graph |
Area under the curve= work |
Negative Work |
Force is in opposite direction of motion |
Basics
A= |
Force on object/ mass of object |
Motion |
Equations |
Efficiency
Efficiency |
Ration of AMA to IMA |
Efficiency = |
AMA/IMA x 100 |
AMA < IMA |
Wout < Win |
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Power
Power |
The time rate of work |
Joule/ second |
watt |
746 watt |
1 horsepower |
Power |
Force x velocity |
Simple Machines
Simple machines |
Any device that varies the effect of an applied force |
1 |
Lever |
2 |
Pulley |
3 |
Wheel + Axel |
4 |
Inclined plane (screw, wedge) |
Lever class 1 |
LFE |
Lever class 2 |
FLE |
Lever class 3 |
LEF |
A machine can |
Redistribute work |
... |
Change size or direction of input force |
... |
Increase output force by change distance the force is applied |
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Energy
Energy |
The ability to do work |
Kinetic Energy |
associated with motion |
KE= |
1/2mv^2 |
Units of KE |
Joules |
KE is directly proportional to V^2 |
A car at 2x speed has 4x kinetic energy |
Change in KE |
Work |
Mechanical Advantage
Actual Mechanical Advantage |
How much a machine multiplies a force |
AMA >1 |
Makes you stronger |
AMA <1 |
Makes you weaker |
IMA |
How a machine would multiply a force if it were 100% efficient |
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