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    (Original post by Namige)
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    To find R, I have to take moments about A. By resolving mg, I can solve it by doing mgcos30 . AB - h . AC = 0

    or, mg . AD - h . AC = 0.
    Huh!

    You want  mg\cos 30.AB-R.AC=0

    or  mg.AD-R.AC=0


    But I'm wondering why you can't do

    mgcos30 . A(CoG) - h.AC = 0
    Because A(CofG) is not at 30 degrees to the horizontal - it's above that angle. And it should be R.AC, not h.AC.

    or mgcos30 . AB - h.AC = 0 . Can someone shed some light on this?
    That's is what you had initially, but should be R.AC, not h.AC.
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    (Original post by ghostwalker)
    Huh!

    You want  mg\cos 30.AB-R.AC=0

    or  mg.AD-R.AC=0




    Because A(CofG) is not at 30 degrees to the horizontal - it's above that angle. And it should be R.AC, not h.AC.



    That's is what you had initially, but should be R.AC, not h.AC.
    Silly me! Thanks.
 
 
 
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