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    hi,
    im doing a write up of a young modulus experiment and im trying to work out the uncertainties in stress and strain and therefore young modulus.
    Please can someone help and explain how to do this
    can you please explain how to calculate the uncertainty in the
    • cross sectional area
    • force
    • stress
    • strain
    • and young modulus
    finally when trying to work out uncertainty in stress do i find the uncertainty in the extension or the scale reading ( what i actually measured)
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    Start with the measurements .

    Look at how these combine to work out each quantity and work through step by step.
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    (Original post by teachercol)
    Start with the measurements .

    Look at how these combine to work out each quantity and work through step by step.
    is there an uncertainty if acceleration due to gravity worth considering when calculating stress?
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    not really - we know the acc due to gravity much more accurately than you can measure stuff in a school/college lab.
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    after more calculations i have worked out some values of uncertainty in stress and strain but should the uncertainty be the same for all stress values because it is for strain and then how do i turn these values into a total uncertainty in my young modulus? please help quickly
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    (Original post by teachercol)
    not really - we know the acc due to gravity much more accurately than you can measure stuff in a school/college lab.
    after more calculations i have worked out some values of uncertainty in stress and strain but should the uncertainty be the same for all stress values because it is for strain and then how do i turn these values into a total uncertainty in my young modulus? please help quickly
 
 
 
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