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    Hi,

    I'm a little confused about this question could someone help me ?

    Calculate the tension in the rope T




    So I did:

    moment = force X distance
    100 X 0.3 = 30

    and

    150 X 0.6 = 90

    So then 30 + 90 = 120Nm

    But the answer says 100N


    Where did I go wrong ?


    Thanks
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    0.3 x 100 + 0.6 x 150 = 1.2 x T
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    Your anticlockwise moments are correct.

    Reconsider the Tension though, if you are taking moments from O (grey blob) and moment = force * distance. What will T equal?

    And then, assuming equilibrium, anticlockwise moments = clockwise moments.
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    (Original post by racshot65)
    So I did:

    moment = force X distance
    100 X 0.3 = 30

    and

    150 X 0.6 = 90

    So then 30 + 90 = 120Nm

    But the answer says 100N


    Where did I go wrong ?


    Thanks
    You haven't finished the question. You've calculated the moment, but you're looking for the tension - a force. As you've already said, moment = force * distance.
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    Ahh thank you I see


    Moment = 120Nm

    moment = force X distance

    so


    Force = moment / distance

    T = 120/1.2 = 100N

    !
 
 
 
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