phy201
Your 'cq_1_01.2' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.
** **
The problem:
Answer the following:
How accurately do you think you can measure the time between two events using the TIMER program?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
I think that the accuracy of the timer program is within .01 of the actual timing. I think that the timer program is more accurate than precise,
because it is manually operated by press the mouse button and there is no way to physically do this with precision.
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
#$&*
What is the shortest time interval you think you would be able to measure with reasonable accuracy?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
I opened the timer program and clicked as quick as I could for two trials. Both trials gave me time intervals that were .2 second apart.
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
#$&*
How does the percent error in timing intervals change as the time between the events gets smaller?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
THe percent error will decrrease as the time between events gets smaller
???????I did this by if my intervals change by .2 per every second .2/1.0s = 20% error if the time is lessoned between intervals .1/1.0s = 10% error..
so the error is decreasing, I juse want top make sure I am corret in thinking here???????????
You're on the right track here.
However the size of the uncertainty doesn't generally decrease as intervals get shorter.
For example your neurological response does not get better with shorter intervals. So you can't expect the uncertaintly associated with that response to decrease. If you have, say, an uncertainty of .1 second when timing a 2-second interval then you have a 5% uncertainty. If you have the same uncertainty when timing a 1-second interval, the the uncertainty is .1 sec / (1 sec) = .10, or 10%. The shorter the interval the greater the uncertainty is as a percent of the timing.
Similarly, even if your neurological response was very consistent (say to within a millisecond, which isn't really possible), the .01 second uncertainty in the timer itself would be the same for any interval. The shorter the interval, the greater percent that .01 second would be (e.g., .01 s / (2 s) = .005 = 0.5%, whereas .01 s / (1 s) = .01 or 1%).
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
#$&*
How accurately are you able to measure the positions of the ball and the pendulum in the initial video?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
I think the ball and the pendulum could be measured accuratly within .1 of a second, but I am not sure???????????????
#$&*
** **
about 15 minutes
** **
not really sure about my answers but I answered the best I could here.
Your thinking and your explanations are very good, and your conclusions follow fromo your assumptions.
However at least one of your assumptions goes a step too far. I believe you'll understand my notes.
See also the discussion at the link below. You'll recognize the note I inserted here in that document. No need for a revision unless you have additional questions, or additional work to which you want me to respond.
Keep up the good work, and continue to ask valuable questions, as you've done on several occasions already.
&#Please compare your solutions with the expanded discussion at the link
Solution
Self-critique your solutions, if this is necessary, according to the usual criteria. Insert any revisions, questions, etc. into a copy of this posted document. Mark any insertions with &&&& so they can be easily identified. &#