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    Hello,

    I am trying to get my head around direct proportion and cant seem to answer this question.



    1. A simple machine has an effort : load ratio of 3 : 37. Determine the effort, in newtons, to lift a load of 5.55 kN.



    Can anyone shed any light
    Thanks
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    a way too look at it is that the "total" is 40, so thats 3 + 37. 37 is the 5.55, so you need to divide that by 37, which conveniently which is easy if you have a calculator. now you know what "1" is, you just need to multiply it by 3, which will be your final answer
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    (Original post by medavidcook)
    1. A simple machine has an effort : load ratio of 3 : 37. Determine the effort, in newtons, to lift a load of 5.55 kN.
    This says that it takes an effort of 3 N to lift a load of 37 N or to put it another way, 3 N corresponds to 37 N i.e.

    effort 3 \text{N} \equiv 37 \text{N} load

    So to what effort does an load of 1 N correspond, if it's a linear relationship? (Hint: how do you go from 37 to 1?)
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    (Original post by Ash1597)
    a way too look at it is that the "total" is 40, so thats 3 + 37. 37 is the 5.55 ..
    The rules of this forum forbid complete answers.
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    (Original post by atsruser)
    The rules of this forum forbid complete answers.
    uh oh, ill edit the post
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    well 5.55 ÷ 37 is 0.15 x by 3 is 1.35 - however the answer should be 450N.

    I just can't seem to get that answer.
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    firstly, 0.15 X 3 is not 1.35.

    you then need to convert that amount of kN to N by multiplying it by 1000, then thats your answer
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    (Original post by Ash1597)
    firstly, 0.15 X 3 is not 1.35.

    also, you sure its not a load:effort ratio? it greatly matters which order round they are. is it effort: load or load: effort?
    Sorry didnt clear calculator

    I copied the question direct from book.
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    (Original post by medavidcook)
    Sorry didnt clear calculator

    I copied the question direct from book.
    right so now hopefully youve got 0.45 kn, now you need to convert that into newtons, by multiplying that by 1000, which gives you...
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    (Original post by Ash1597)
    right so now hopefully youve got 0.45 kn, now you need to convert that into newtons, by multiplying that by 1000, which gives you...
    Yeh i have thanks
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    (Original post by medavidcook)
    Yeh i have thanks
    nice one
 
 
 
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