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ch 8 terms adam
|occurs when a force causes an object to move in the direction of the force
|Work is ONLY done when …………
|the force is in the same direction that the object is going
|These 2 things must be present in order for work to be occurring
|work and force
|What is the work formula ?
|W= F x D
|What is the power formula?
|Watt include picture(s)
|The unit used to express power
|Machine include picture(s)
|a device that helps make work easier by changing the size or direction of a force
|the work you do on a machine
|The work done by the machine
|When can work output be GREATER than work input? – it can never be greater.
|(carefully read last paragraph p. 193)
|“Machines don’t save work” . True or false? Explain your answer
|False. The same work is done either way
|Mechanical Advantage –tells you how many times the machine multiplies force
|Mechanical Advantage formula –MA= output force/input force
|What are the 6 simple machines ?
|Lever, screw, wedge, pulley, wheel and axle, inclined plane
|Lever –simple machine consisting of a bar that pivots at a fixed point
|Examples of include picture(s)
|see saw, kayak, wheel barrow
|Fulcrum –the point on a level where the bar pivots
|Examples of each of the 3 classes of levers
|simple machine that is a straight, slanted surface
|How do you increase the mechanical advantage of an inclined plane?
|the longer the inclined plane is compared with its height, the greater the mechanical advantage
|Examples of Inclined Planes include picture(s)
|a double inclined plane that moves.
|Examples of Wedges include picture(s)
|an inclined plane that is wrapped in a spiral
|Examples Screws include picture(s)
|jar lid, screw
|How do you change the mechanical advantage of a screw?
|the longer the inclined plane the higher the mechanical advantage
|Wheel & Axle
|a simple machine consisting of two circular objects of different sizes
|Examples of Wheel & Axle include picture(s)
|Pulley –a simple machine consisting of a grooved wheel that holds a rope or a cable
|Examples of Pulleys include picture(s)