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Data handling

  1. Mar 24, 2007 #1
    1. The problem statement, all variables and given/known data

    Basically i have been given a set of data to analyse. The data was collected by rolling a ball of a ramp. The ramp is set on a table and the edge of the ramp is parralel to the table. The ball then travels through the air until it hits a piece of carbon paper. The vertical displacement is then measured and recorded in relation to the horizontal displacement which is the spacing from the edge of the ramp to the board with the carbon paper on. This is the data that i have been given.
    0.100 2.0 6.5 10.0 14.0 14.5
    0.200 18.5 48.5 53.5 51.0 47.0
    0.300 57.0 60.0 64.5 90.5 94.5
    0.400 118.5 134.5 160.5 168.0 159.0
    0.500 210.5 228.0 228.0 217.0 241.0
    0.600 336.0 394.5 356.0 348.5 392.5
    0.700 447.0 501.0 514.0 558.0 532.5
    0.800 587.5 683.0 714.0 601.0 605.5

    the first colum is the horizontal displacement in meters the other 4 colums are the 5 tests carried out with the horizontal displacment at the set value. These are the different vertical displacments in mm from that horizontal displacment.

    Basically iIknow that there are alot of anomolies in the data and I want to remove them so I can produce an accurate average.

    2. Relevant equations

    Im not sure if this would help but i produced an equation to work out the vertical displacment at different horizontal displacements. y being the vertical displacement and x being the horizontal displacement. I also assumed that all potential energy is converted into kinetic energy which is obviously not true

    y=gx^2/2v^2 g being the the value for the gravitational field strength

    3. The attempt at a solution[/b

    I first tried to remove the anomolies visually from the table removing the ones which didnt seem to fit with the other ones but this gave me a terrible average graph which wasnt smooth at all. At the moment I am trying to use the formulas to work out error bars but as i have mad the assumption that all potential energy is converted into kinetic this doesnt work.

    Help would be much appreciated Thanks J
  2. jcsd
  3. Mar 24, 2007 #2
    have you got a statistical calculator? If not I would try plotting the means along with error bars on semi-log paper. try to get a best fit, and see what the slope is.
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