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: **
10cm,17.4cm
7.40cm
I got the number in the second line by taking the difference of the numbers in the first line. These numbers are the ones used to measure the rubber band. I also marked the rubber band with one mark with a black permanent marker. I believe the accuarcy to be within +-.04
** The basis for your uncertainty estimate: **
I did not use a reduced ruler. I found it easier to use the normal size roller taking the measurement. I found that most of the rubber bands were close enough to the mm mark that I could get to within +-.05
** Positions of the ends of each rubber band, actual lengths of each when the chain supports 1 domino: **
10cm,17.40cm
10cm,17.35cm
10cm,17.40cm
10cm,17.55cm
10cm,17.50cm
10cm,17.40cm
end
7.40cm,7.35cm,7.40cm,7.55cm,7.50cm,7.40cm
Each rubber band was marked with a black marker. The 1st rubberband had one mark the second rubber band had two marks and so on.
Uncertainty is +-.05
** Distances between ends when supporting 2 dominoes **
7.55cm,7.50cm,7.65cm,7.80cm,7.70cm,7.60cm
These are the measurements for two dominoes
** Lengths when supporting 4, 6, ... dominoes: **
7.80cm,7.70cm,7.80cm,8.00cm,7.90cm,7.90cm
4
8.05cm,7.90cm,8.10cm,8.20cm,8.30cm,8.10cm
6
8.20cm,8.10cm,8.20cm,8.30cm,8.40cm,8.35cm
8
8.40cm,8.30cm,8.45cm,8.55cm,8.60cm,8.50cm
10
end
** Your table of force in Newtons vs. length in cm for all rubber bands **
7.80cm,7.70cm,7.80cm,8.00cm,7.90cm,7.90cm,.19newtons
8.05cm,7.90cm,8.10cm,8.20cm,8.30cm,8.10cm,.38newtons
8.20cm,8.10cm,8.20cm,8.30cm,8.40cm,8.35cm,.76newtons
8.40cm,8.30cm,8.45cm,8.55cm,8.60cm,8.50cm,.95newtons
end
starting from left to right column 1 is the 1st rubber band length in cm and so on to column six which is the sixth rubber band. The final column 7 is the force put on each rubber band which is measured in newtons
** Describe the graph of your first rubber band **
My curve seems to be increasing at a fairly constant rate. its kinda back and fourth between points.
All six rubber bands were stretched. They looked like a rubber band that was stretched a little bit
end
** The tension force in your first rubber band at length 9.8 cm: **
1.6newtons
** The length of your first rubber band when tension is 1.4 N: **
8.50cm
** 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: **
I dont under stand this. I dont see how the curve effects the force.
** 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: **
7.30cm,7.60cm,7.90cm,8.30cm
.10cm,.05cm,.10cm,.10cm
** The typical error you estimate when predicting force for a given length from your graphs: **
Probally the values from the curve because there was a some human error in getting these lengths. I believe the curve gives me smoother flow from one point to another.
+-2, by looking at my graph and how I can break down the section between .19 and .38 with little tick marks .
** The typical error you estimate when predicting length for a given force from your graphs: **
+-.10,same as above breaking it down between section 7.00cm and 7.50cm
** **
2hrs
** **
On this question listed below I did my estimate on 8.6cm because my rubber band measurements was not close to this so my graph was not that big.
Estimate the force in Newtons corresponding to a length of 9.8 cm and report the number in the first line of the box below?
&#Very good work. Let me know if you have questions. &#