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    I know that if value a is raised to the power n then the percentage uncertainty = n*(delta a/a)*100 but what if n = 1/k (k where is any number greater than 1). What do i do?
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    (Original post by SorryInAdvance)
    I know that if value a is raised to the power n then the percentage uncertainty = n*(delta a/a)*100 but what if n = 1/k (k where is any number greater than 1). What do i do?
    It's still times n.
    If you have a square root (power half) then the % uncertainty is halved.
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    (Original post by Stonebridge)
    It's still times n.
    If you have a square root (power half) then the % uncertainty is halved.
    Does logs affect the value?
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    (Original post by SorryInAdvance)
    Does logs affect the value?
    Yes.
    If you have loge of a number N with an uncertainty ±n it's done as follows
    x = loge (N ± n)
    Gives Loge N ± n/N

    So if you have a length measured as, say, 50m ± 2m
    Then the uncertainty in the loge is just 2/50
    Giving Loge(50) ± 2/50
    Giving 3.91 ± 0.04
 
 
 
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