Phy 121
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 got faster
** Your description of the rhythm of the pendulum when tilted 'forward' **
the rhythm gets even faster towards the end before it stops
** Your description of the process used to keep the rhythm steady and the results you observed: **
i tilted the bracket forward a little so the pearl wasnt touching the bracket. the rhythm was then steady once i released the pearl. it hit the bracket 6 times.
** Your description of what happened on the tilted surface (textbook and domino), rotating the system 45 degrees at a time: **
on the first try the sounds get closer together. after the first 45 degree turn the sounds are similar to the first. after the second 45 degree turn the sounds seem to keep constant. the next 45 degree turn the sounds get closer together. the next 45 degrees it was also close. and the last two 45 degree turns were pretty constant.
** Your description of how you oriented the bracket on the tilted surface to obtain a steady rhythm: **
it would have to be parallel to the book sides
** Your report of 8 time intervals between release and the second 'hit': **
0.563
0.531
0.593
0.531
0.584
0.567
0.533
0.597
its how long it took from the time i released the pearl to the time it took for it to hit twice.
** Your report of 4 trials timing alternate hits starting with the second 'hit': **
0.781, 0.719, 0.883
0.842, 0.794, 0.821
0.795, 0.812, 0.854
0.804, 0.865, 0.798
i observed every time the pearl hit the bracket every other time.
** The length of your pendulum in cm (you might have reported length in mm; the request in your instructions might have been ambiguous): **
4.5cm
** Your time intervals for alternate 'hits', starting from release until the pendulum stops swinging: **
0.81,0.80,0.84
** Your description of the pendulum's motion from release to the 2d hit: **
when the pearl hits the bracket, there isnt as much force coming back off of the bracket, thats why the rhythm gets faster.
** Your description of the pendulum's motion from the 2d hit to 4th hit: **
release and first hit, there was much more time between those two than from the first and 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: **
there is a greater time period between the release and second hit than the second and fourth hit
** 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: **
the motions from the 2nd to 4th hit are less frequent than those between the 4th and 6th hit
** Your conjecture as to why a clear difference occurs in some intervals vs. others: **
because its from the release
** What evidence is there that subsequent intervals increase, decrease or remain the same: **
increase
** What evidence is there that the time between 'hits' is independent of the amplitude of the swing? **
it would be for the hypothesis, the times would be a lot smaller had my pendulum been smaller
** **
1 hour
** **
Nice work. You appear to have excellent data.