Your 'rubber band calibration' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.
** Your initial comment (if any): **
** first line ruler markings, distance in actual cm between ends, how obtained: **
0.00, 7.21
7.21
.05
Just as a comment, i had to use the regular size ruler as opposed to the smalller one simply because I conducted my experiment at my job where I had very few of my materials and, for time's sake, did it when it was convenient.
** The basis for your uncertainty estimate: **
I just feel that as a result of how hard it is to hold the string of bands and measure too that my results are fairly accurate but not entirely so.
** Positions of the ends of each rubber band, actual lengths of each when the chain supports 1 domino: **
0, 7.21
0, 7.15
0, 7.40
0, 7.43
0, 7.50
0, 7.52
END
7.21, 7.15, 7.40, 7.43, 7.50, 7.52
6,5,4,3,2,1
.05
** Distances between ends when supporting 2 dominoes **
7.40, 7.45, 7.46, 7.60, 7.62, 7.50
These differences were the result of the weight of 2 dominoes.
** Lengths when supporting 4, 6, ... dominoes: **
7.71, 7.60, 7.75, 7.92, 7.80, 7.90
4
8.04, 7.91, 8.00, 8.15, 8.03, 8.10
6
8.12, 8.03, 8.16, 8.38, 8.18, 8.28
8
8.45, 8.43, 8.39, 8.62, 8.50, 8.92
10
8.90, 8.72, 8.61, 9.00, 8.83, 9.03
12
9.42, 9.48, 9.0, 9.45, 9.52, 9.47
14
END
** Your table of force in Newtons vs. length in cm for all rubber bands **
7.21, 7.15, 7.40, 7.43, 7.50, 7.52
.19
7.40, 7.45, 7.46, 7.60, 7.62, 7.50
.38
7.71, 7.60, 7.75, 7.92, 7.80, 7.90
.76
8.04, 7.91, 8.00, 8.15, 8.03, 8.10
1.14
8.12, 8.03, 8.16, 8.38, 8.18, 8.28
1.52
8.45, 8.43, 8.39, 8.62, 8.50, 8.92
1.9
8.90, 8.72, 8.61, 9.00, 8.83, 9.03
2.28
9.42, 9.48, 9.0, 9.45, 9.52, 9.47
2.66
END
The first column in the table is the length of the rubber band (in centimeters). The second column number is the force that the weight of the dominoes is exerting on the rubber band (measured in Newtons).
** Describe the graph of your first rubber band **
increasing at a constant rate throughout
increasing at a cosntant rate, then at increasing rate
increasing at constant rate throughout
increasing at a constant rate then at increasing rate
increasing at an increasing rate throughout
increasing at an increasing rate throughout
** The tension force in your first rubber band at length 9.8 cm: **
3.4 Newtons
** The length of your first rubber band when tension is 1.4 N: **
8.15 cm
** The forces at your observed lengths the 1st rubber band, as given by the curve, and the deviations of those curve-predicted lengths from the observed lengths: **
1.95, 2.00, 2.20, 2.85, 3.20
The points differ by about .5 from the actual weight supported.
** The lengths predicted for forces .19 N, .38 N, .76 N, 1.14 N, etc. by the curve for your first rubber band; the deviations of your actual observations from these predictions: **
7.60, 7.75, 7.90, 8.20, etc.
The lengths for this graph were basically the same because, on this graph, the points fell into a nearly perfect line. The only exception was the 2.66 Newton point which caused the length to differ a bit from the actual value because the actual value lies slightly below the line.
** The typical error you estimate when predicting force for a given length from your graphs: **
I have more faith in the curve, because the curve minimizes error with the data. My uncertainty would be within .05, and I feel that it would be potentially this inaccurate simply because of the diffulties associated with measuring the stretchy bands and such.
** The typical error you estimate when predicting length for a given force from your graphs: **
I think the uncertainty would be within .5. I chose this number because my graphs seemed to be fairly accurate but not so much as to think they might not be off by this much. When I tested a couple of numbers uring the graph, thye were within the .5 cm mark, as in, the real numbers for the data were within .5 cm of my curved line.
** **
1 hour
** **
Your work here looks very good.