Question

Lever: Effort Force vs Resistance force 400 350 Z 300 250 200 150 100 50 0 4.0204x 2.5579 R2 0.9985 0 20 40 60 80 100 Effort Force (N)

A worker lifts various loads with the same lever. The distance of the applied force from the fulcrum is 4.00 m and the distance from the fulcrum to the load is 0.750 m. A graph of resistance force vs. effort force 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? Show your work.

Answer 1

Efficiency = Mechanical advantage (AMA) / Ideal Mechanical Advantage (IMA)
The mechanical advantage = Load force / Applied force
The ideal mechanical advantage = 1 , because the IMA is always the amount of beneficial 'structures', towards the increasing the efficiency.
So, given that (Load)Force1 X (Load)Length1 / (Applied)Force2 X (Applied)Length2 = AMA
Therefore AMA = (F(0.750m)) / (F(4.00m)) = 0.1875
Since AMA = 0.1875 , and IMA = 1
% Eff = AMA / IMA = 0.1875 / 1.00 = 0.1875 = 18.75% Efficient



So the answers are...
Mechanical advantage = 0.1875
Ideal mechanical advantage = 1
Efficiency of the lever = 0.1875 or 18.75%