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: **
0 cm, 12.00 cm
0 cm, 12.00 cm
Those numbers are the actual distances between the end points of the rubber bands, rather than just the ruler positions given in the first line. I believe my measurements are accurate to the +-0.05.
** The basis for your uncertainty estimate: **
The basis is because the ruler actual measures to the 0.1, which means I am estimating the 0.01 place.
** Positions of the ends of each rubber band, actual lengths of each when the chain supports 1 domino: **
0, 12.02
0, 11.91
0, 11.62
0, 11.85
0, 11.55
0, 11.61
12,11.91, 11.62, 11.85, 11.55, 11.61
+-0.05 cm uncertainty
** Distances between ends when supporting 2 dominoes **
12.30, 12.10, 11.70, 12.00, 11.60, 11.80
Rubber band distances from end to end for each domino
** Lengths when supporting 4, 6, ... dominoes: **
12.33, 12.51, 12.24, 12.52, 12.25, 12.46
4
12.62, 12.21, 12.56, 12.76, 12.32, 11.85
6
13.11, 13.11, 12.92 12.98, 12.61, 12.42
8
13.55, 13.45, 13.28, 13.48 13.01, 12.65
10
** Your table of force in Newtons vs. length in cm for all rubber bands **
12.00,11.91, 11.62, 11.85, 11.55, 11.61
0.19
12.30, 12.10, 11.70, 12.00, 11.60, 11.80
0.38
12.33, 12.51, 12.24, 12.52, 12.25, 12.46
.76
12.62, 12.21, 12.56, 12.76, 12.32, 11.85
1.14
13.11, 13.11, 12.92 12.98, 12.61, 12.42
1.52
13.55, 13.45, 13.28, 13.48 13.01, 12.65
1.9
** Describe the graph of your first rubber band **
The graph appears to be increasing at an increasing rate, then increasing at a decreasing rate.
The first rubber band is stretched the most. Then, each subsequent rubber band is stretched less and less the further down the line. end
** The tension force in your first rubber band at length 9.8 cm: **
0.09
** The length of your first rubber band when tension is 1.4 N: **
13 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: **
0.17, 0.35, 0.73, 1.03, 1.49, 1.87
0.02, 0.03, 0.03, 0.11, 0.03, 0.03
** 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: **
12.00, 12.10, 12.35, 12.76, 13.3, 13.58
0, 0.20, 0.02, 0.14, 0.19, 0.03
** The typical error you estimate when predicting force for a given length from your graphs: **
The values I reported in my table, because although they are not perfect, they are better than using a best fit line in this situation. I would say the uncertainty is +-0.05 because I used a y scale of 0.3 which is a quite a small scale and can be estimated more closely.
** The typical error you estimate when predicting length for a given force from your graphs: **
I would say there is an uncertainty of about +-0.03, because I used an x scale of 0.2, which means I can make a reasonable estimate and not be more than likely more than 0.03 off.
** **
3 hours
** **
Your work on this experiment is very good.