#$&*
Phy 201
Your 'cq_1_00.1' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.
** **
The problem:
You don't have to actually do so, but it should be clear that if you wished to do so, you could take several observations of positions and clock times. The main point here is to think about how you would use that information if you did go to the trouble of collecting it. However, most students do not answer these questions in terms of position and clock time information. Some students do not pause the video as instructed. To be sure you are thinking in terms of positions and clock times, please take a minute to do the following, which should not take you more than a couple of minutes:
Pick one of the videos, and write down the position and clock time of one of the objects, as best you can determine them, in each of three different frames. The three frames should all depict the same 'roll' down the ramp, i.e. the same video clip, at three different clock times. They should not include information from two or more different video clips.
For each of the three readings, simply write down the clock time as it appears on the computer screen, and the position of the object along the meter stick. You can choose either object (i.e., either the pendulum or the roll of tape), but use the same object for all three measurements. Do not go to a lot of trouble to estimate the position with great accuracy. Just make the best estimates you can in a couple of minutes.
Which object did you choose and what were the three positions and the three clock times?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
Video 1 of the smaller files and the three positions and times were: 59.36 seconds 2 inches, 59.9 seconds 15 inches, and 60.12 seconds 19 inches
#$&*
In the following you don't have to actually do calculations with your actual data. Simply explain how you would use data of this nature if you had a series of several position vs. clock time observations:
If you did use observations of positions and clock times from this video, how accurately do you think you could determine the positions, and how accurately do you think you would know the clock times? Give a reasonable numerical answer to this question (e.g., positions within 1 meter, within 2 centimeters, within 3 inches, etc; clock times within 3 seconds, or within .002 seconds, or within .4 seconds, etc.). You should include an explanations of the basis for your estimate: Why did you make the estimate you did?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
I dont think I could get accurate positions because the tape measure is very hard to see, I could probably get within 1 inch, but I do think I could get accurate time because the timer is very clear and when pausing it, it gives me the time within .001 seconds.
#$&*
How can you use observations of position and clock time to determine whether the tape rolling along an incline is speeding up or slowing down?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
To determine whether the tape is speeding up or slowing down, we can use the position it is at and the time and see how long it takes to get a certain amount of inches at the top compared to further down the incline.
#$&*
How can you use observations of position and clock time to determine whether the swinging pendulum is speeding up or slowing down?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
To determine whether the pendulum is speeding up or slowing down, we can use the position it is at and the time and see how long it takes to get a certain amount of inches from one side compared to the other side.
#$&*
Challenge (University Physics students should attempt answer Challenge questions; Principles of Physics and General College Physics may do so but it is optional for these students): It is obvious that a pendulum swinging back and forth speeds up at times, and slows down at times. How could you determine, by measuring positions and clock times, at what location a swinging pendulum starts slowing down?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
#$&*
Challenge (University Physics students should attempt answer Challenge questions; Principles of Physics and General College Physics may do so but it is optional for these students): How could you use your observations to determine whether the rate at which the tape is speeding up is constant, increasing or decreasing?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
#$&*
*#&!
&#This looks very good. Let me know if you have any questions. &#
Task: `q014.
If you submit a document and get a form confirmation, then the document has been received.
It might happen that you submit a document then realize you didn't submit your identifying information. If this happens, then submit it once more, and be sure to carefully include your information. However, do your best to get it right the first time.
Please respond with a statement detailing your understanding of the process of submitting a document.
**** Your response (insert your response beginning in the next line; the next line is blank and doesn't include the #$... prompt):
Once a document is submitted you receive a form confirmation.
#$&* (your response should have gone on the line above this one)
*#&!
&#This looks good. Let me know if you have any questions. &#
After the 'Your Answer' prompt below, insert your answers to the following :
Describe how you constructed your pendulum and out of what (what you used for the mass, its approximate dimensions, what it is made of, what sort of string or thread you used--be as specific as possible).
Describe its motion, including an estimate (you don't have to measure this, just give a ballpark estimate) of how far it swung from side to side and how this distance varied over the time you counted.
Describe what you mean by a 'cycle'. Different people might mean different things, but there are only a couple of reasonable meanings. As long as you describe what you mean we will all understand what you measured.
'Frequency' means the number of cycles in a unit of time. Your counts are frequencies, in cycles/minute. 'Period' means time required for a cycle. Explain how you used your observed frequencies to obtain the periods of the nine pendulums in this experiment.
Your answer (start in the next line):
I constructed my pendulum out of tiny string and a ring. The ring was my high school class ring so it was white gold and didnt weigh much at all. I used very thin white thread; something like you would pull out of a shirt. It swung very short, probably 3 inches back and forth when I did the very first length, but my last length swung probably 10-12 inches back a forth. I counted a cycle as the ring going over and back was one. I divided 60 seconds by how every many times my pendulum cycled.
#$&* explanations with std terminology
*#&!
&#Your work on this lab submission looks good. See my notes. Let me know if you have any questions.
Revision isn't requested, but if you do choose to submit revisions, clarifications or questions, please insert them into a copy of this document, and mark your insertions with &&&& (please mark each insertion at the beginning and at the end).
Be sure to include the entire document, including my notes. &#