Help on this moments question?

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    Can someone tell me how you're supposed to find the moment about A? The answer's supposed to be 9.39 N in the clockwise direction but I can't get that
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    (Original post by selenacxoxo)
    Can someone tell me how you're supposed to find the moment about A? The answer's supposed to be 9.39 N in the clockwise direction but I can't get that
    Perpendicular distance * Force

    Clockwise M(A): 4.6 \cdot 1.9 + 2.1\cdot 5.2

    Anticlockwise M(A): 1.3 \cdot 7.9

    Find the resultant moment.
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    (Original post by RDKGames)
    Perpendicular distance * Force

    Clockwise M(A): 4.6 \cdot 1.9 + 2.1\cdot 5.2

    Anticlockwise M(A): 1.3 \cdot 7.9

    Find the resultant moment.
    Thank youuuuuuuu but can I ask why you'd calculate the moment of the 5.2N and 7.9N forces? I thought they were acting parallel to A?
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    (Original post by selenacxoxo)
    Thank youuuuuuuu but can I ask why you'd calculate the moment of the 5.2N and 7.9N forces? I thought they were acting parallel to A?
    They are, and they have an effect on A. What about them?
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    (Original post by RDKGames)
    They are, and they have an effect on A. What about them?
    Ohhhh never mind I was just confused
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    (Original post by selenacxoxo)
    Ohhhh never mind I was just confused
    The only forces you can ignore are those acting from A, so like the 6.4N, if that's what you're asking.
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    (Original post by RDKGames)
    Perpendicular distance * Force

    Clockwise M(A): 4.6 \cdot 1.9 + 2.1\cdot 5.2

    Anticlockwise M(A): 1.3 \cdot 7.9

    Find the resultant moment.
    How do you know that the 7.9N force is anticlockwise but the 5.2 force is clockwise?
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    (Original post by AspiringUnderdog)
    How do you know that the 7.9N force is anticlockwise but the 5.2 force is clockwise?
    Observation. Imagine yourself having this contraption of whatever. Put one finger on A, and apply forces with the other hand on their respective positions. In which direction do you think will the contraption turn?? That's how I do it anyway, I'm quite visual with this stuff.
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    (Original post by RDKGames)
    Observation. Imagine yourself having this contraption of whatever. Put one finger on A, and apply forces with the other hand on their respective positions. In which direction do you think will the contraption turn?? That's how I do it anyway, I'm quite visual with this stuff.
    Ah okay thanks that really helps.
    Down forces turn downwards and in this case is anticlockwise and vice versa for the up force!
    Thanks, dude.
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    (Original post by RDKGames)
    The only forces you can ignore are those acting from A, so like the 6.4N, if that's what you're asking.
    Yeah I think I get it now, thanks for the help 😊
 
 
 
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