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Phy 241
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.
** CQ_1_00.1_labelMessages **
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about 45 to 1 hour
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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: ->->->->->->->->->->->-> scussion (start in the next line):
Black clip, 1 foot 2-3 inches; 40.687
5-6 inches; 41.234
1 foot 1-2 inches; 42.109
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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: ->->->->->->->->->->->-> scussion (start in the next line):
You could use the information to see how much time it would take to get from one end to the other; over many trials you could find the speed it
is slowing at and how long it would take it to stop.
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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: ->->->->->->->->->->->-> scussion (start in the next line):
You can determine the speed vs distance between each inch or so and compare to find out if the speed is increases or decreasing.
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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: ->->->->->->->->->->->-> scussion (start in the next line):
As I stated in the intro over time you can compare the distance the pendulum travels vs the time it takes to get from on peak to the other.
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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: ->->->->->->->->->->->-> scussion (start in the next line):
In the swing down, te pendulum speed would increase, whereas when it inclines up, it will slow a bit.
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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: ->->->->->->->->->->->-> scussion (start in the next line):
Initial time and start point vs 2 or 3 mid-way points and final time and ending point; compare time and distance between each of the points and
you should be able to determine how the speed is acting.
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&#Good responses. Let me know if you have questions. &#