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Levers A lever is a bar that is free to turn about a fixed point called the fulcrum which supports the lever. A lever increases force and makes the work easier. Every lever has an effort arm ( dist. from effort force to fulcrum) and a resistance arm (dist. from resistance force to fulcrum).
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How does a lever work? Section 5-3 Levers A lever is a bar that
is free to turn about a fixed point called the fulcrum which
supports the lever. A lever increases force and makes the work
easier. Every lever has an effort arm ( dist. from effort force to
fulcrum) and a resistance arm (dist. from resistance force to
fulcrum). MA = effort arm length/resistance arm length.
Mechanical Advantage MA = effort armlength/resistancearm length.
First-class levers The fulcrum is between the effort and the
resistance. Crowbar, hammer, scissors. First-class levers
Second-class levers The resistance isbetween the effortand the
fulcrum.Wheel barrel, bottleopener, nut cracker. Second-class
levers Third-class levers The effort isbetween thefulcrum and
theresistance. Bat,fishing pole, tennisracket, tweezers,shovel.
Third-class levers H.W. p.81 check/apply 1-8 wkst. 5-3 p. 81
activity lever lab