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: **
95 % sure I already sent this file, because I know I already did it, but I can't find my back up, so I am going to do it over, so I can finish lab 10's experiment.
This does not show among the file containing lab submissions. When did you send it?
** Your description of the rhythm of the pendulum when tilted 'back' **
The rhythm gets faster.
** Your description of the rhythm of the pendulum when tilted 'forward' **
the sounds get closer together.
** Your description of the process used to keep the rhythm steady and the results you observed: **
I placed 1 domino under the base, it was on the side that was farest from the ball.
** Your description of what happened on the tilted surface (textbook and domino), rotating the system 45 degrees at a time: **
base of bracket parallel = closer
45 degrees = further
90 degrees = most far (barely made contact)
135 degrees = further
180 degrees = consistant (overall closer)
** Your description of how you oriented the bracket on the tilted surface to obtain a steady rhythm: **
use the 180 degree. In this config the base is slightly inclined at an angle about 45 degrees. This gives a very consistant beat.
** Your report of 8 time intervals between release and the second 'hit': **
.992
1.100
.992
.883
.758
.883
.992
.879
I obtained these numbers by simultaneously dropping the pendulum and hitting the timer button, allowing it to hit once, and then pressing the timer button a second time once it hits the second time.
** Your report of 4 trials timing alternate hits starting with the second 'hit': **
.941, .758, .988, .938
.938, .878, .941
.883, .719, .879
.992, .820, .930
I obtained these results by following the instructions above, it was hard for me to get it to bounce more than 4 times however, because I did not receive any copper wire in my kit.
** The length of your pendulum in cm (you might have reported length in mm; the request in your instructions might have been ambiguous): **
6.8 cm
** Your time intervals for alternate 'hits', starting from release until the pendulum stops swinging: **
.140, .141, .05
** Your description of the pendulum's motion from release to the 2d hit: **
When the ball is released from the extreme point it begins a semi oscillation path, where it meets the base, it then reflects and is projected back towards the extreme.
** Your description of the pendulum's motion from the 2d hit to 4th hit: **
semi-oscillation. Very quickly gets pulled with the string towards a path of oscillation, hits base, and quickly shots back up to extreme, looked kinda like it surpassed the extreme, then comes back down and strikes base this time going up but not all the way to the extreme.
** 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: **
Between release and second hit and forth hit takes more time then between initial and second. the inital and 2nd hit cover more ground at a faster velocity.
&#A full cycle of a free pendulum is from extreme point to equilibrium to opposite extreme point then back to equilibrium and finally back to (almost) the original extreme point. The pearl pendulum is released from an 'extreme point' and strikes the bracket at its equilibrium point, so it doesn't get to the opposite extreme point.Thus the period of the pendulum can be divided into four parts. From the steadiness of the rhythm we have good evidence that the motion between 'hits' takes the same time independent of the amplitude of the motion (the rhythm remains constant while the amplitude of the motion decreases). Theoretically each of the four parts of the cycle, as described above, takes the same time. Assuming this to be true, we can speak of the quarter-cycle from an extreme point to equilibrium or from equilibrium to an extreme point.
Through how many quarter-cycles does the pendulum move between release and the second 'hit'?
Through how many quarter-cycles does it move between the second and the fourth 'hit'?
What therefore should be the ratio of the time interval from 2d to 4th 'hit', to the interval from release to the 2d 'hit'?
How does this ratio compare with the results you just reported?
Does this constitute evidence for or against the theoretical hypothesis that the quarter-cycles all require the same time?Suggested response title: description of motion of pearl pendulum &#
&#Please respond with a copy of this question, a copy of any other part of this document you wish to include, and your response to the question. Indicate your response using the symbols *&##. As your title use the 'response title' suggested above (just copy and paste that title into the Title box of the Submit Work form); if no suggested title was given use your own title.
&#
** 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: **
betwen the 4th and 6th hit takes the most time, and between 2nd and 4th hit on avg takes the least time.
** Your conjecture as to why a clear difference occurs in some intervals vs. others: **
because of gravity, and we are dropping it with a v0 of 0. Every other time it goes to an extreme and then has to come to a complete stop before it comes back down.
** What evidence is there that subsequent intervals increase, decrease or remain the same: **
the time would increase.
** What evidence is there that the time between 'hits' is independent of the amplitude of the swing? **
because the length completly controls how far it will actually swing. it cannot swing more then the given length.
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1.5 hrs
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&#Please respond as requested to the question posed in my notes so we can more specifically interpret these results.
&#