rubber band calibration

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: **

10,17.14

7.14

I got this number from subtracting the measurement reading at the beginning and the reading at the end. this rubber band is marked 1

I think the limits are with in 0.02cm

** The basis for your uncertainty estimate: **

I am reading the ruler in mm which gives me accracy to 0.1cm, but I can estimate the distance between two mm mark to give and estimate to 0.01cm but eastimating a fraction of distance between mm marks I would estimate as being 0.02cm.

** Positions of the ends of each rubber band, actual lengths of each when the chain supports 1 domino: **

10,17.14

10,17.01

10,17.22

10,17.18

10,17.20

10,17.05

7.14,7.01,7.22,7.18,7.2,7.05

1,2,3,4,5,6

0.02cm

** Distances between ends when supporting 2 dominoes **

7.49,7.22,7.31,7.37,7.3,7.25

this is for 2 dominoes

** Lengths when supporting 4, 6, ... dominoes: **

7.65,7.51,7.48,7.42,7.49,7.40

4

7.85,7.52,7.61,7.64,7.62,7.54

6

7.91,7.71,7.73,7.72,7.80,7.70

8

8.11,7.80,7.92,7.91,7.89,7.87

10

8.32,7.99,8.16,8.13,8.06,8.09

12

8.49,8.21,8.30,8.26,8.31,8.19

14

8.61,8.31,8.41,8.42,8.49,8.29

16

8.79,8.60,8.63,8.66,8.71,8.57

18

9.01,8.71,8.90,8.92,8.93,8.89

20

end

I ran out of dominoes before my stretched length was increased by 30%

** Your table of force in Newtons vs. length in cm for all rubber bands **

7.14,7.01,7.22,7.18,7.20,7.05,0.19

7.49,7.22,7.31,7.37,7.30,7.25,0.38

7.65,7.51,7.48,7.42,7.49,7.40,0.76

7.85,7.52,7.61,7.64,7.62,7.54,1.146

7.91,7.71,7.73,7.72,7.80,7.70,1.52

8.11,7.80,7.92,7.91,7.89,7.87,1.90

8.32,7.99,8.16,8.13,8.06,8.09,2.28

8.49,8.21,8.30,8.26,8.31,8.19,2.66

8.61,8.31,8.41,8.42,8.49,8.29,3.04

8.79,8.60,8.63,8.66,8.71,8.57,3.42

9.01,8.71,8.90,8.92,8.93,8.89,3.80

end

My lengths are measured in cm and the force is measured in Newtons

** Describe the graph of your first rubber band **

The best fit line on on my graph fro rubberband #1 would be a slight curve that is increasing at a decreaseing rate.

All of my graphs are similar to the first rubberband. I used excel to create all of my graphs and to add trendlines to best fit the points.

** The tension force in your first rubber band at length 9.8 cm: **

None of my rubberbands stretched out this much.

9.8 cm would be more than a 30% stretch for all of my rubberbands, so I would not have had any lengths this long

** The length of your first rubber band when tension is 1.4 N: **

7.90 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: **

0.4,0.75,1.25,1.4,1.85,2.3,2.7,3,3.4,3.8

0.02,0.01,0.11,0.12,0.05,0.02,0.04,0.04,0.02,0

** 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: **

7.5,7.65,7.8,7.95,8.15,8.3,8.46,8.65,8.82,9

0.01,0,0.05,0.04,0.04,0.02,0.03,0.04,0.03,0.01

** The typical error you estimate when predicting force for a given length from your graphs: **

I have more faith ion the values from the curve because it automatically adjusts for errors that might be present.

I would an estimate of uncretainty of +/- 0.04N. Which is the average difference between actual and estimate

** The typical error you estimate when predicting length for a given force from your graphs: **

I would an estimate of uncretainty of +/- 0.03cm. Which is the average difference between actual and estimate

** **

2 hr 30 min

** **

Very good work.