Phy 121
Your 'pendulum counts in-class' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.
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Report one line per observation. Each line should consist the length of the pendulum being observed, the 1-minute count and the scale factor by which your reported length should be multiplied to get the length of the pendulum in centimeters. The three requested quantities should be separated by commas. Each line should therefore consist of three numbers, separated by commas. Don't include any words, units, or other information in any of these lines.
You may report as many lines as possible. Use the space below.
Your data report (start on the next line):
9.5, 54 ,2.2
19, 42 ,2.2
38, 31 ,2.2
Add your description of how you made your observations. Include an explanation of how much uncertainty there was in each observation, and explain how you arrived at your uncertainty estimate.
Your explanations (start on the next line):
Once I measured my first length of string, I tried to measure out the length using units that were about the length from the end of my (index) finger to the first joint in my finger, which came to be about 9.5 units. I then approximated that my specified length was equal to about 2.2 cm (sort of guessing). For each experiment, I held the pendulum at about the center of my chest, and held it out to my left, then let go. After it would go a complete cycle, I started my timer (a small kitchen timer) and counted the number of cycles. After each experiment I doubled the length of my string. I’d say that my uncertainty would be to give or take about a half of a cycle, since in the experiment I would round half cycles up or down depending on whether it was in backswing or fore swing respectively.
Good responses. Let me know if you have questions.