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: **

5 3/8 in, 5 1/8 in

3 in

Measured the length of the actual rubber band. It is marked number one.

** The basis for your uncertainty estimate: **

I believe the paperclips could have played a role in the net length of the rubber band.

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

4 7/8, 4 7/8

3 - II

End

4 7/8, 4 7/8

3 - III

End

5 1/4, 5 1/4

3 1/8 - IV

End

** Distances between ends when supporting 2 dominoes **

3, 3, 2 15/16, 3 1/8

Results of the weight of two dominoes.

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

3 1/4, 3 1/8, 3 1/8, 3 1/4

4

3 3/8, 3 1/4, 3 1/4, 3 3/8

6

3 5/8, 3 3/8, 3 3/8, 3 5/8

8

3 15/16, 3 5/8, 3 5/8, 3 15/16

10

End

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

3, 3, 3, 3 1/8, 0.19

3, 3, 2 15/16, 3 1/8, 0.38

3 1/4, 3 1/8, 3 1/8, 3 1/4, 0.76

3 3/8, 3 1/4, 3 1/4, 3 3/8, 1.14

3 5/8, 3 3/8, 3 3/8, 3 5/8, 1.52

3 15/16, 3 5/8, 3 5/8, 3 15/16, 1.9

End

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

I - Increasing at a decreasing rate

II - Increasing at a constant rate

III - Increasing at a constant rate

IV - Inreasing at a decreasing rate

End

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

1.71 Newtons

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

8.89 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: **

3, 0.19

3, 0.38

3 1/4, 0.76

3 3/8, 1.14

3 5/8, 1.52

3 15/16, 1.9

** 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: **

3, 0.19

3, 0.38

3 1/4, 0.76

3 3/8, 1.14

3 5/8, 1.52

3 15/16, 1.9

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

I would trust the graph more than the values in my table because the graph would be a better overall estimate.

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

+- 1/16

** **

40 minutes

** **

You would have been better off measuring lengths in cm, but your data appears to be good.