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Find F such that the moment around A will not exceed 1000N*m for any value of θ.
M = fd
The Attempt at a Solution
I got the right answer, I found the distance of a -> b
AB= √( (2^2) + (3^2) )
and then I did
M = fd
1000 = f (3.6)
f = 277.8 N
This is correct according to the answer in the back, but I don't understand why.
1. I was under the impression for: M = fd , d must be the perpendicular distance. Clearly, the d we are using is not perpendicular to f. Does d not have to be perpendicular to the force?
2. I thought this was a trick question at first, and logically I thought it made most sense that the greatest moment around A would be caused by a force only in the vertical direction. So I tried doing it where Fx = 0 and Fy is the variable of interest.
So i tried, M = (Fy)d
1000 = (Fy)(3)
but the fy I get is clearly not the answer. Can someone explain this to me.
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