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Homework Statement
In order to lift the 30 kg mass, a Force F is applied to the massless meter stick shown below. How much weight must the fulcrum bear if the mass is to be lifted?
Homework Equations
R/E = l/L
The Attempt at a Solution
So I began with the formula above and this is my set up:
300/F = 0.25/0.75. I got 900 N for F. However, the problem asks about the fulcrum. Logically I would add the 900 N with the 300 N of the resistance force by the mass, I get 1200 N. Since the answer is 400 N, it appears that I have to divide the Force lever arm distance to determine the force on the fulcrum? I think this is the right reasoning here but would appreciate any insight in to this problem.
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