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tweety1234
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Homework Statement
A uniform rod AB of length 4m and mass 2kg is suspended in a horizontal position by two vertical strings attached at points p and Q where AP=1m and AQ=3m. When a particle of mass 3kg is attached at point R of the rod, the rod is on the point of turning about point P. Calculate the distance AR.
The Attempt at a Solution
As the rod is on the point of tilting about P than, Rp =0
I have drawn the diagram and have attached with this post, but i am not sure it is correct, and also I am not quite sure were to put point 'R' on my diagram.
the moments equation that I have come up with is;
taking moments about P
[tex] 2kg + 3kg (xm-3m)=0 [/tex]
[tex] 2 \times 9.8 + 3 \times 9.8 (xm-3m) =0 [/tex]
[tex] 19.6 + 29.4x-88.2=0 [/tex]
[tex] 29.4x-68.2=0 [/tex]
[tex] 29.4x=68.2 [/tex]
[tex] x = 2.3 [/tex]
I think my moments equation is wrong, or my diagram, can anyone please show me where i am going wrong
thanks!
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