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Question
Solution
A crowbar is a class I lever, Thus its fulcrum lies in between the load and effort
Given, load, L = 500 kgf
Lenght of crowbar = 4 m = 400cm
Therefore, load arm = 50 cm
Effort arm = 400 - 50 cm = 350 cm
Let effort = E
Now, M.A = `"effort arm"/"load arm" = 350/50` = 7
Also, M.A = `"L"/"E"`
7 = `500/"E"`
or, E = 71.4 kgf
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