phy 201
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: **
1, 8.7
7.70
i measured from the 1 cm mark to the 8.7 cm mark from the top of the first rubber band to the bottom of the first rubber band. number is accurate to within +/- .03 cm. the band is marked with 1 dash.
** The basis for your uncertainty estimate: **
within .05 off so +/- .025.
** Positions of the ends of each rubber band, actual lengths of each when the chain supports 1 domino: **
1.0, 8.7
1.0, 8.6
1.0, 8.4
1.0, 8.4
1.0, 9.3
1.0, 8.4
end
7.70, 7.60, 7.40, 7.40, 8.30, 7.40
|, ||, |||, ||||, |||||, ||||||
+/- .03
** Distances between ends when supporting 2 dominoes **
7.80, 7.70, 7.50, 7.60, 8.50, 7.60
these lengths are in cm and were from the weight of two dominoes.
** Lengths when supporting 4, 6, ... dominoes: **
8.00, 7.80, 7.70, 7.70, 8.80, 7.90
4
8.30, 8.10, 7.90, 7.90, 9.00, 8.10
6
8.50, 8.30, 8.10, 8.20, 9.40, 8.40
8
end
** Your table of force in Newtons vs. length in cm for all rubber bands **
7.70, 7.60, 7.40, 7.40, .19
7.80, 7.70, 7.50, 7.60, .38
7.90, 7.80, 7.70, 7.70, .57
8.00, 7.80, 7.70, 7.70, .76
8.20, 8.00, 7.80, 7.90, .95
8.30, 8.10, 7.90, 7.90, 1.14
8.40, 8.20, 8.00, 8.10, 1.33
8.50, 8.30, 8.10, 8.20, 1.52
end
the lengths are measured in cm out to two decimal places. the final number in each line is in newtons.
** Describe the graph of your first rubber band **
the lines were all increasing, but at some points they were increasing at an increasing rate and increasing at a decreasing rate. none of the lines were ever decreasing.
end
** The tension force in your first rubber band at length 9.8 cm: **
4.0
** The length of your first rubber band when tension is 1.4 N: **
8.42
** 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: **
.2, .4, .6, .8, 1.0, 1.2, 1.4, 1.5
not too far off.
** 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: **
7.7, 7.8, 7.88, 7.95, 8.15, 8.23, 8.39, 8.5
not too far off.
** The typical error you estimate when predicting force for a given length from your graphs: **
the values from the curve, simply because they smooth the transition from measurement to measurement, in case of error.
+/- .03 N, i broke the force side of the graph up into lines of .165 on 5mm graph paper.
** The typical error you estimate when predicting length for a given force from your graphs: **
+/- .05 cm, i broke the length side of the graph up into lines of .1 cm on 5mm graph paper.
** **
2.5 hours
** **
&#Very good responses. Let me know if you have questions. &#