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Homework Help: RMS uncertainty using a Trend Line

  1. Oct 12, 2011 #1
    1. The problem statement, all variables and given/known data

    Find the acceleration of gravity. Using the trendline equation of Force v. hanging mass, find the RMS uncertainty for the force.

    Trend line equation: y = 9.8968x - 0.0342 R² = 0.9493

    Data Values:

    Hanging mass is the first number. Force is the second number.
    0.40 3.839928
    0.39 3.690708
    0.37 3.720552
    0.35 3.720552
    0.30 2.765544
    0.20 1.949808


    2. Relevant equations

    F=ma
    RMS = Sqrt((X1)2+(X2)2+(X3)2+........+(XN)2/N)


    3. The attempt at a solution

    I got 9.8968 as the accleration of gravity.

    I got 3.35414 as the RMS of the Force values.

    I also got 6.566915632 as the RMS of the Force-Force (trendline)

    I just don't understand how to calculate the RMS uncertainty of force. I don't know what numbers should i use.

    Thanks
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
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