# This is my question, How many pounds of force must a man exert on one end of a 9foot lever to lift a 250 pound rock on the other end, if the fulcrum is 2feet from the rock?

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To answer your question properly , I would need to know how far the fulcrum is from the load . From there , it is a simple ratio with respect to the length of your 9ft. lever . For example : if your fulcrum is placed in the exact center (4.5 feet) of the 9ft. lever , it would require 250 pounds of effort plus the energy required to overcome gravity to lift 250lbs. of weight . Now , put the fulcrum 50% closer to the load (2.25feet) and your effort required will be 50% less , or 125lbs.

Posted on Oct 08, 2010

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