Levers

 

Purpose of Levers:

            Levers work with the strength that the operator applies to the job in order to do more work.

 

Examples of Levers:

            Seesaws, balance scales, scissors lifts, bottle openers, fishing poles.

How to Use Levers:

  Levers have three parts: Fulcrum, Effort, and Load.

·   Fulcrum is the place that the lever rocks back and forth, or the pivot point.

·   The Effort is the amount of force the operator has to apply.

·   The Load is the object to be lifted or lowered.

·   When the fulcrum is in the middle of the lever the amount of effort the operator pushes down equals exactly the amount of the load lifted on the other end.

·   When the fulcrum is closer to the load the operator does not have to push down as hard to lift the same weight, the difference is the operator will have to push down a longer distance.  

·   There are three classes of levers.

·   In the First Class Lever the fulcrum is in the middle with effort on the left and load on the right.

·   In the Second Class Lever the load is in the middle with the fulcrum on the left and effort on the right. 

·   In the Third Class Lever the effort is in the middle with fulcrum on the left and load on the right.

 

 

 

 

Church, R. Jok, Beckman & Jax,

http://www.beakman.com/lever/lever.html.  (1999).

 

 

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