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Homework Help: Lab Question (spring formula)

  1. Oct 17, 2005 #1
    i have this error formula

    1/2 (change in m/m + change in k/k) * square root of m/k

    now my question is

    the m in the m/k is that in kg or grams

    and the m in the change in m/m is that in grams or kg

    my classmates are having mixed results, im confused, want to kow the real way
  2. jcsd
  3. Oct 17, 2005 #2
    the real formula were trying to prove

    2 (pie) * root of m/k

    the m was in KG so im assuming in the error its in KG too right
  4. Oct 18, 2005 #3
    noone ?!
    please ppl
  5. Oct 18, 2005 #4
    Hey, I believe the formula you have is one used to calculate the period of an oscillating mass-spring system.

    Anyway, in order to obtain clear working, we normally express all physical quantities in SI units. The SI unit for mass is kg, and I suppose if you used kg as the unit for mass in your calculations, the error will also be in kg.

    Hope this helps!
  6. Oct 18, 2005 #5


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    Homework Helper

    Delta m / m is unitless ... so is Delta k /k !
    They must be, because you add them!

    By the way: HERE, Delta means "uncertainty", not change.
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