RRCS MOBILE
 BACK VARIOUS NOTES: SIMPLE MACHINES Chapter 4 summary WORK- force acting over a distance to move an object JOULE- unit of work and energy POWER- rate at which work is done WATT- unit of power (1 joule per second) MACHINE- device that makes work easier by changing distance or direction of the force  WORK INPUT- work that goes in a machine and is exerted over a distance WORK OUTPUT- work that comes out of the machine and is exerted over a distance EFFICIENCY- comparing work input to the work output MECHANICAL ADVANTAGE- number of times a machine multiple the effort force IDEAL MECHANICAL ADVANTAGE- The more efficient a machine is, the closer it is to this EFFORT- force exerted on a machine FORCE- push or pull FRICTION- acts on an object to make it slow down or stop PITCH- distance between the threads of a screw RESISTANCE- force to be over come by a machine 1. INCLINED PLANE: flat surface that is higher at one end and it multiples force 2. WEDGE: inclined plane that moves (example – ax) 3. SCREW: inclined plane that is wrapped around a pole or cylinder to form a spiral 4. LEVER: bar to freely move around a single point 5. PULLEY: rope, belt or chain wrapped around a wheel, change amount or direction of force 6. WHEEL AND AXLE: a larger circle and a small circle placed next to each other to work together 7. COMBINATION MACHINE: two or more simple machines that are working together Formulas:  Work=force x distance Work is measured in joules or newton/meters Force is measured in newtons ***KNOW THAT A MACHINE ONLY DECREASES THE AMOUNT OF WORK THAT YOU DO, NOT THE TOTAL AMOUNT OF WORK DONE. THAT REMAINS THE SAME!!! ***KNOW THAT an inclined plane wrapped around a cylinder is called a SCREW ***KNOW THAT in a screwdriver, the handle is the wheel and the shaft is the axle. It is actually a wheel and axle!!! ***KNOW THAT in order to do WORK, an object MUST BE MOVED as a result of force!!! Distance is measured in meters POWER = WORK/TIME Power is measured in WATTS WORK IS MEASURED IN JOULES TIME IS MEASURED IN SECONDS
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