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Homework Help: Question about uncertainties

  1. Sep 11, 2009 #1
    1. The problem statement, all variables and given/known data

    A glider moves on a level (horizontal) air track. The motion detector records five velocities of the glider: 0.48 m/s, 0.48 m/s, 0.53 m/s, 0.48 m/s, 0.47 m/s. The average velocity, uncertainty in the velocity, and relative uncertainty are

    2. Relevant equations
    Avg velocity= V1+V2+V3+V4+V5/2

    3. The attempt at a solution
    For the average velocity I used the above equation and got 0.488. For the uncertainty in the velocity I did 0.53-0.47/2 to get plus or minus 3, but I'm not sure if that is right. I have no idea on how find the relative uncertainty
  2. jcsd
  3. Sep 11, 2009 #2
    Ok so I just read that relative uncertainty is found by percent uncertainty in velocity/ avg value. Correct? but when I use that my answer is'nt one of my choices. So is there something wrong I did when finding the percent uncertainty in the velocity?
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