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    I just wanted to clarify if the solution is wrong or not.

    The question:

    A 9 m long non-uniform beam, AB, of weight 240 N, is suspended between two trees to make a walkway. It is held in equilibrium by vertical wires at C and D. The magnitude of the tension in the wire at C is twice the magnitude of the tension in the wire at D.

    I solved part a) but part b) is:

    Find the distance of the centre of mass of the beam from A.

    This is what the diagram looks like:
    Spoiler:
    Show

    Name:  IMG_1344.JPG
Views: 13
Size:  57.0 KB


    I did as what the solution showed, but I had a 7 instead of the 8, because the beam is 9 m long and the mid section of the diagram would be 7? To make a total of 9, by adding the 1 m near A and the 1 m near B.
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    (Original post by Student1914)
    I just wanted to clarify if the solution is wrong or not.

    The question:

    A 9 m long non-uniform beam, AB, of weight 240 N, is suspended between two trees to make a walkway. It is held in equilibrium by vertical wires at C and D. The magnitude of the tension in the wire at C is twice the magnitude of the tension in the wire at D.

    I solved part a) but part b) is:

    Find the distance of the centre of mass of the beam from A.

    This is what the diagram looks like:
    Spoiler:
    Show



    Name:  IMG_1344.JPG
Views: 13
Size:  57.0 KB




    I did as what the solution showed, but I had a 7 instead of the 8, because the beam is 9 m long and the mid section of the diagram would be 7? To make a total of 9, by adding the 1 m near A and the 1 m near B.
    The solution is taking moments about A. D is 8 m from A.

    Where were you taking moments about? If you take moments about C, there won't be a term involving Tc, the term involving Td will be Td x 7 and the distance you work out won't be from A so you'll have to add 1.
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    (Original post by tiny hobbit)
    The solution is taking moments about A. D is 8 m from A.

    Where were you taking moments about? If you take moments about C, there won't be a term involving Tc, the term involving Td will be Td x 7 and the distance you work out won't be from A so you'll have to add 1.
    I did do it from A. I realised my mistake once you said: "D is 8m from A". Sorry! What a silly mistake...
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    (Original post by Student1914)
    I did do it from A. I realised my mistake once you said: "D is 8m from A". Sorry! What a silly mistake...
    No problem. One of my efforts earlier today involved saying that 2.1 + 9.1 = 10.2
 
 
 
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