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FIRST CLASS LEVERS

FIRST CLASS LEVERS SEE-SAW LEVERS

1stClass Lever -The fulcrum is located betweenthe eort arm and the resistance arm.

First class levers can multiply force and distance

Examples scissors! see-saw! hammer"s claws! pliers! etc#

L2 effort arm > L1- load arm

Mechanical advantage is more than one

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FIRST CLASS LEVERS

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SECOND CLASS

LEVERS

2ND

CLASS LEVERS WHEELBARROW LEVERS$ndClass Lever - resistance is located betweenthe eort arm and the fulcrum. These leversmultiply the force but the direction stays the

same.Example wheelbarrow! stapler! bottle opener!%n&er nail clippers! nut crac'er

L2 effort arm > L1- load armMechanical advantage is more than one

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SECOND CLASS

LEVERS

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THIRD CLASS

LEVERS

L2 effort arm < L1- load arm

Mechanical advantage is less than one

Not recommended in

engineering practice

(rdClass Lever -The eort force is located betweenthe fulcrum and the resistance. The eort arm isalways shorter than the resistance arm so it cannotmultiply the force and the )* is always less than 1.

Examples ra'e! hoc'ey stic'! broom! shovel! %shin& pole!twee+ers! ton&s

3RDCLASS LEVERS - TWEEZERS

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THIRD CLASS

LEVERS

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