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, 21.8cm
7.61cm
Numbers measured on the first line using the single-reduction ruler, then converted to the number on the second line. For the single reduction rule, 4 actual cm(acm) = 6.2 reduced cm(rcm), so 1 actual cm = 1.55 reduced cm. So 11.8rcm* 1acm/1.55rcm= 7.61cm. Limited to +-.06cm because 1acm=15.5rmm, and 1/15.5= .06
** The basis for your uncertainty estimate: **
Uncertainty due to not looking at the rulers directly straight on as possible, movement in chain, subtle movement in ruler while looking from one measurement to the next, calculators rouding up or down while coverting, and possible distortions in the reduced rules.
** Positions of the ends of each rubber band, actual lengths of each when the chain supports 1 domino: **
10, 21.8
10, 21.8
10, 21.8
10, 21.8
10, 21.8
10, 21.8
End
7.61, 7.61, 7.61, 7.61, 7.61, 7.61cm
1, 2, 3, 4, 5, 6
Uncertainty due to not looking at the rulers directly straight on as possible, movement in chain, subtle movement in ruler while looking from one measurement to the next, calculators rouding up or down while coverting, and possible distortions in the reduced rules.
** Distances between ends when supporting 2 dominoes **
7.68, 7.68, 7.68, 7.74, 7.68, 7.68cm
Results are from the weight of 2 dominoes.
** Lengths when supporting 4, 6, ... dominoes: **
8.00, 8.00, 8.00, 8.00, 7.87, 7.87cm
4
8.26, 8.13, 8.13, 8.13, 8.00, 8.00cm
6
8.39, 8.32, 8.32, 8.32, 8.32, 8.32cm
8
8.39, 8.39, 8.39, 8.39, 8.39, 8.39cm
9
End
** Your table of force in Newtons vs. length in cm for all rubber bands **
7.61, 7.61, 7.61, 7.61, 7.61, 7.61cm, .19N
7.68, 7.68, 7.68, 7.74, 7.68, 7.68cm, .38N
8.00, 8.00, 8.00, 8.00, 7.87, 7.87cm, .76N
8.26, 8.13, 8.13, 8.13, 8.00, 8.00cm, 1.14N
8.39, 8.32, 8.32, 8.32, 8.32, 8.32cm, 1.52N
8.39, 8.39, 8.39, 8.39, 8.39, 8.39cm, 1.71N
End
The table shows how much the bands length was stretched and at what force. Length in cm and Force in Newtons.
** Describe the graph of your first rubber band **
Increasing at a steady rate, then increasing at an increasing rate.
Increasing at a steady rate, then increasing at an increasing rate. Increasing at a steady rate, then increasing at an increasing rate.
Increasing at a steady rate, then increasing at an increasing rate.
Increasing at a steady rate, then increasing at an increasing rate.
Increasing at a steady rate, then increasing at an increasing rate.
End
** The tension force in your first rubber band at length 9.8 cm: **
1.71N/8.39cm= x/9.8cm=>(1.71*9.8)/8.39= 1.99N
** The length of your first rubber band when tension is 1.4 N: **
8.37m
** 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, .29, .76, 1.14, 1.52, 1.71N
.00, -.09, .00, .00, .00, .00N
** 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: **
7.61, 7.74, 8.00, 8.26, 8.52, 8.66cm
0.00, +.06, 0.00, 0.00, +.13, +.27cm
** The typical error you estimate when predicting force for a given length from your graphs: **
I have motre faith in the values from my table, because that is WHAT IS versus what IS SUPPOSED TO BE.
There are unavoidable errors in reading your instruments. It depends on the situation, but if the thing you are measuring is governed by a smooth curve, and if most of the data fluctuations result for unavoidable uncertainties, the 'smoothed' information provided by a well-fit curve can be more reliable.
I would say force within +-.02 because thats the what I got when I took the amount I was off the curve by and divided by 6.
** The typical error you estimate when predicting length for a given force from your graphs: **
Length I would say +-.08 because thats the what I got when I took the amounts I was off the curve by and divided by 6.
** **
2Hrs15min
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&#This looks very good. Let me know if you have any questions. &#