A man lifts various loads with the same lever. The distance of the applied force from fulcrum is 2.00 m and the distance from the fulcrum to the load is .5oo m. A graph of force vs. resistance is shown. What is the mechanical advantage of the lever? What is the ideal mechanical advantage of the lever? What is the efficiency of the lever?

Question

adamk · Answer

Ideal Advantage = length(force side) / length(load side)
= 2.00 m / 0.500 m
= 4 (engineering units cancel out)

For efficiency of the lever you need actual data.
Divide actual mass of the load by actual force applied
Divide 4 (Ideal advantage) by this number and you will get a number less than or equal to 1.

Convert this number into a percentage and you have the efficiency.