Your 'pearl pendulum' 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 general comment, if any: **
** Your description of the rhythm of the pendulum when tilted 'back' **
The rhythm is getting faster with each tap. The duration of time between each tap is decreasing.
** Your description of the rhythm of the pendulum when tilted 'forward' **
The rhythm becomes slower. The duration of time between each tap is increasing.
** Your description of the process used to keep the rhythm steady and the results you observed: **
To balance the bracket to get the pendulum to bounce constant, I used one of the washers as a shim to level the bracket. The rhythm of the taps against the bracket were steady and the pendulum had more taps against the bracket than in the other two observations. I got 11 bounces in this observation.
** Your description of what happened on the tilted surface (textbook and domino), rotating the system 45 degrees at a time: **
By placing 2 dominoes at the top left and right corner of my textbook, I was able to use my textbook as a tilted surface. Then I started placing my bracket at 0 deg by facing the pearl with the right side of the book. I tapped the pearl against the bracket to see the frequency of the taps. Then I rotated it 45 deg and tested it at each 45 deg interval until I reached 360 deg (1 full rotation). Here is the data I collected:
0 deg, constant
45 deg, faster
90 deg, faster
135 deg, faster
180 deg, constant
225 deg, slower
270 deg, slower
315 deg, slower
** Your description of how you oriented the bracket on the tilted surface to obtain a steady rhythm: **
I would orient the bracket at the 0 deg and 180 deg points to get the most constant rhythm.
** Your report of 8 time intervals between release and the second 'hit': **
When releaing the pendulum, I simultaneously clicked the mouse to start the timer and then clicked it a second time when the pearl tapped the bracket for the second time. In line 9, I got a recorded measurement of .4804s
** Your report of 4 trials timing alternate hits starting with the second 'hit': **
.7414, .7109, .8398, .7921
.5312, .7109, .7414, .8125
.7804, .8125, .7296
.7109, .6718, .6523
** The length of your pendulum in cm (you might have reported length in mm; the request in your instructions might have been ambiguous): **
The length of the pendulum is 14cm.
** Your time intervals for alternate 'hits', starting from release until the pendulum stops swinging: **
.69, .73, .74
** Your description of the pendulum's motion from release to the 2d hit: **
You release the pendulum from an extreme point at which it goes back to its equillibrium point. Then it goes back toward its extreme point, but does not reach the extreme point again.
** Your description of the pendulum's motion from the 2d hit to 4th hit: **
From first hit to the second hit, the pendulum moves very fast, and sways about 2/3 of way back to the extreme point, before heading back toward the equillibrium point for a second hit.
** Your description of the difference in the pendulum's motion from release to the 2d 'hit', compared to the motion from the 2d 'hit' to the 4th hit: **
After the second hit the pendulum seems to stablize more and begins to enter a rhythym of taps that are almost constant.
** Your description of the difference in the pendulum's motion from the 2d to the 4th 'hit' compared to the motion from the 4th to 6th hit: **
Between the 2nd and 4th hit to between the 4th and 6th hit, I do not notice a change. At this point the pendulum seems to be in a constant rhythm.
** Your conjecture as to why a clear difference occurs in some intervals vs. others: **
The first time interval would be different because of the rapid acceleration and speed of the pendulum that it picks up and the force that it strikes the bracket with that will kick it back out with the same force until it begins to dampen down for its 3rd and 4th hit.
** What evidence is there that subsequent intervals increase, decrease or remain the same: **
It depends of the position of the bracket.
** What evidence is there that the time between 'hits' is independent of the amplitude of the swing? **
I believe the hypothesis that the length of the pendulum swing is dependent on its length and not how far it swings. Reason, i believe this is no matter how far I tried to pull the pearl back and let it strike the braket the pattern never changed. However, changing the position and length of the pendulum change the time interval/rhythm of the taps against the bracket.
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1hr and 17 min
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Good results and good answers. Let me know if you have questions.