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Propagation of uncertainty

  1. Oct 18, 2014 #1
    Hello.
    I have measured the period of the pendulum
    T=2.18 +/- 0.02

    which is consistent with the true period 2.19865... so I expect myself to find a consistent value of g if I apply the formula propagating the error in the right way.

    I get
    g=9.96 +/- 0.2


    Why?
     
  2. jcsd
  3. Oct 18, 2014 #2
    Assuming you are referring to a simple pendulum what is it's length, and the error in that measurement? The final calculated value for g will involve both errors .
     
  4. Oct 18, 2014 #3
    Thanks for your reply. Length is 1.20 meter without error. I'm training myself with a simulation on computer. The problem here is calculation, I discovered that usually to find g, we find the slope of the line L = g/4pi^2 * T^2
    I also noticed that if i take T = 2.20 and T = 2.16, and I calculate g, the real value is between them.
     
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