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28 Cards in this Set
- Front
- Back
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pulley
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a modified lever consisting of a rope that moves around a grooved wheel; can be movable or fixed
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distance principle
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states that any reduction in the effort force will be paid for by an increased distance through which that force must act
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lever
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a rigid bar capable of turning about a fulcrum
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mechanical advantage (M.A.)
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the amount by which a machine magnifies effort (force)
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law of moments
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the method for computing the amount of force exerted by levers with unequal arms;
w(1)d(1) = w(2)d(2) |
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block and tackle
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an arrangement of fixed and movable pulleys connected by ropes; has a high mechanical advantage
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second-class lever
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a lever in which the resistance is located between the fulcrum and the effort
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watt (W)
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the SI unit of power; 1 joule of energy per second
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scientific idealization
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approximating an answer when an extremely accurate one is not needed
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third-class lever
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a lever in which the effort is applied between the fulcrum and the resistance
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effort arm
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the distance from the fulcrum to the effort
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pitch
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the distance between two adjacent threads on a screw; how high or low a tone sounds to an observer (related to frequency)
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screw
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an inclined plane would around a cylinder or cone
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inclined plane
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a slanted surface used to raise object
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joule (J)
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the SI unit of energy; equal to 1 Newton-meter of work
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inclined plane
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a slanted surface used to raise objects
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efficiency
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the percent of work input returned as useful output
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wheel and axle
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modified lever in which the effort arm and the resistance arm revolve around a central fulcrum
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power
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the amount of work done in a given period of time
P = W/t |
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effort
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the force that must be applied to a simple machine to make it produce work
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resistance arm
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the distance from the fulcrum to the resistance
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resistance
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the force against which a simple machine works; opposition to the flow of electrons
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simple machines
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One or two part devices that make work easier: lever, wheel and axle, pulley, inclined plane, wedge, screw
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torque
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when the law of moments is not being met and there is pivoting on the fulcrum
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first-class lever
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a lever in which the fulcrum is located between the effort and the resistance
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work
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the product of the force applied on an object multiplied by the distance the object moved;
w= F x d |
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fulcrum
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the fixed point about which a lever turns
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wedge
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two inclined planes placed "back-to-back"
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