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: **
10, 17.6
7.60
+/- .05cm
** The basis for your uncertainty estimate: **
With the ruler held at the starting point of the ruberband, and measured to the other end, there is much room for uncertainty. The fact that my ruler is only marked down to 1mm resolution, I can only estimate to a +/- .05cm accuracy. Also the fact that rubberbands are hanging in mid-air makes it harder to measure them and not have some sort of paralax error involved in the user's judgement. There is much more that I can think of, but the uncertainities do not apply at this point.
** Positions of the ends of each rubber band, actual lengths of each when the chain supports 1 domino: **
10cm, 17.6cm
10cm, 17.4cm
10cm, 17cm
10cm, 17.5cm
10cm, 17.8cm
END
7.60cm, 7.45cm, 7.00cm, 7.45cm, 7.85cm
I, II, III, IV, V
+/- .05
** Distances between ends when supporting 2 dominoes **
7.85cm, 7.50cm, 7.25cm, 7.70cm, 7.85cm
I, II, III, IV, V
+/- .05
** Lengths when supporting 4, 6, ... dominoes: **
8.00cm, 7.75cm, 7.65cm, 8.00cm, 8.00cm
4
8.15cm, 7.85cm, 7.85cm, 8.15cm, 8.25cm
6
8.45cm, 8.05cm, 8.05cm, 8.35cm, 8.65cm
8
8.60cm, 8.35cm, 8.35cm, 8.75cm, 8.95cm
10
END
** Your table of force in Newtons vs. length in cm for all rubber bands **
7.6cm, 7.45cm, 7.00cm, 7.45cm, 7.85cm, 0.19N
7.85cm, 7.50cm, 7.25cm, 7.70cm, 7.85cm, 0.38N
7.85cm, 7.50cm, 7.25cm, 7.70cm, 7.85cm, 0.57N
8.00cm, 7.75cm, 7.65cm, 8.00cm, 8.00cm, 0.76N
8.15cm, 7.85cm, 7.85cm, 8.15cm, 8.25cm, 1.14N
8.45cm, 8.05cm, 8.05cm, 8.35cm, 8.65cm, 1.52N
8.60cm, 8.35cm, 8.35cm, 8.75cm, 8.95cm, 1.90N
END
Each line represents measurements collected by measuring rubberbands that were holding a bag with x-amount of dominoes in it. The final number in each line represents the number of dominoes times the .19 Newtons of force the Earth's gravity exerts on the dominoes.
** Describe the graph of your first rubber band **
All of the graphes look like the graph of a tanget function. However, there are differences in each. Rubberband #3 seems to increase at a constant rate, and almost creates a perfect line. Graphs for Rubberbands #1 and #4 like near identical, with not much stretch with the first few dominoes, and then they increase at an increasing rate. Graphes #2 and #5 are pretty similiar. Not as near identical as #1 and #4, but still very similiar reactions. During the measurements with the first few dominoes, 2 and 5 do not react much; but after 4 dominoes, the rubberbands begin to increase at an increasing rate.
END
** The tension force in your first rubber band at length 9.8 cm: **
3.952N
** The length of your first rubber band when tension is 1.4 N: **
8.31cm
** 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: **
.19, .62, .62, .874, 1.13, 1.64, 1.90
0, +.24, +.05, +.11, -.01, +.12, 0
** 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: **
7.6cm, 7.71cm, 7.82cm, 7.93cm, 8.15cm, 8.38cm, 7.85cm
0, -.14, -.03, -.07, 0, -.07, 0
** The typical error you estimate when predicting force for a given length from your graphs: **
I have more faith in the measurements that I took myself, b/c they are proven by my test; but the calculations are only estimates. For an estimate, I would give it an uncertainty of +/- .10. Reason for this estimate is that most of my estimate are pretty close to the measured values.
** The typical error you estimate when predicting length for a given force from your graphs: **
To calculate force, I would estimate and uncertainty of +/- .15 based on my calculations.
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2 hr 00 min
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&#Good work. Let me know if you have questions. &#