Phy 201
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 sounds get closer.
** Your description of the rhythm of the pendulum when tilted 'forward' **
Sounds get further part. the ping it makes get softer
** Your description of the process used to keep the rhythm steady and the results you observed: **
When I first put the lab together I glued the pearl at the top and run the thread through so the bottom pearl would set about a paper thickness away from the bracket. When I set it on the table it was pretty much level and had a consistent tone.
** Your description of what happened on the tilted surface (textbook and domino), rotating the system 45 degrees at a time: **
I started out with the pendulum facing south which is the bottom of the incline and rotated the pendulum assembly counter clockwise 45deg at a time until I got back to the starting position.Compare the book to a clock and psotion the pendulum at 6,7-8,9,10-11,12,1-2,3,and between 4-5 o'clock
At 6 o'clock the sound got further apart.
Between 7-8 o'clock the sounds got a little closer.
9 o'clock the sounds were pretty constant.
Between 10-11 o'clock sounds got closer
12 o'clock sounds got even closer.
1-2 o'clock the sounds got further apart
3 o'clock sound got constant.
4-5 o'clock the sounds got futher away
** Your description of how you oriented the bracket on the tilted surface to obtain a steady rhythm: **
I would place it between the 9 o'clock and 10 o'clock positon
** Your report of 8 time intervals between release and the second 'hit': **
.502
.502
.460
.502
.531
.521
.475
The are the time intervals for the intial starting point of the pendulum to the second hit of the pearl hitting the bracket.These numbers were obtained by clicking the timer when the pearl was released and stopped at the second hit point. The time intervals are listed from trial one to the last trial
** Your report of 4 trials timing alternate hits starting with the second 'hit': **
.580,.592,.631,.631
.560,.601,.580,.633
.580,.621,.621,.601
.580,.590,.630,.621
these numbers are the time intervals between each second hit. the first row is for trial #1 going from left to right is the first click and to the last click and so on for the rest of the rows
** The length of your pendulum in cm (you might have reported length in mm; the request in your instructions might have been ambiguous): **
9.2cm
** Your time intervals for alternate 'hits', starting from release until the pendulum stops swinging: **
.575,.601,.616
** Your description of the pendulum's motion from release to the 2d hit: **
The pearl pendulum was from the starting extreme point and strikes its equilibrium point which is these bracket and bounces back near its extreme starting point
The pendulum doesn't hit the bracket and its extreme point. There should be more to your description.
** Your description of the pendulum's motion from the 2d hit to 4th hit: **
It was a closer cycle to the bracket then from the intial release and the first 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: **
As with the above situation the pendulums cycle gets closer to the bracket everytime
your previous description was 'The pearl pendulum was from the starting extreme point and strikes its equilibrium point which is these bracket and bounces back near its extreme starting point'. That description fell a little short, per my previous note, that you are describing the motion in the requested terms. This description should be of a similar nature.
** 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 cycle of the pendulum barely comes off the bracket.
** Your conjecture as to why a clear difference occurs in some intervals vs. others: **
Because of timing of the intial release and it has more speed from the release point
** What evidence is there that subsequent intervals increase, decrease or remain the same: **
acording to the time intervals the time increased but the lab is not that accurate.
You appear to have reasonable accuracy. If the times were indeed increasing, then you hadn't quite achieved the specified condition that the rhythm be uniform. The apparent lengthening of the period is therefore not what we are observing here.
Based on your descriptions of the motion, what should be the ratio between the intervals you observed from release to the second 'hit', to the intervals you observed between the subsequent 'hits'? Do your data reveal the expected ratio?
** What evidence is there that the time between 'hits' is independent of the amplitude of the swing? **
The swing of the pendulum depends on the length of the string because the swings get smaller as it goes.
** **
1hr 20min
** **
Very good data. However you have misinterpreted one of the instructions.
&#Please see my notes and submit a copy of this document with revisions and/or questions, and mark your insertions with &&&&. &#