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Phy 241
Your 'ball down ramp' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.
** Ball Down Ramp_labelMessages **
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Timing Ball down Ramp
The picture below shows a ball near the end of a grooved steel track (this steel track is a piece of 'shelf standard'); the shelf standard is supported by a stack of two dominoes. Your lab materials package contains two pieces of shelf standard; the shelf standard shown in the figure is white, but the one in your kit might be colored black, gold, silver or any of a variety of other colors.
If a ball rolls from an initial state of rest down three ramps with different slopes, the same distance along the ramp each time, do you think the time required to roll the length of the ramp will be greatest or least for the steepest ramp, or will the interval on the steepest ramp be neither the greatest nor the least? Explain why you think you have correctly predicted the behavior of the system.
Your answer (start in the next line):
I believe that the time required to roll the length of the ramp will be least for the steepest ramp because the more steeper, the fast the ball will travel.
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If we write down the slopes from least to greatest, next to the time intervals observed for those slopes, would you expect the time intervals to be increasing or decreasing, or do you think there would be no clear pattern? Explain why you think you have correctly described the behavior of the numbers in the table.
Your answer (start in the next line):
I believe that the time intervals to decrease the ball will be moving in a faster rate at the greatest slope.
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Set up the shelf standard ramp on a reasonably level table, using a piece of 30-cm shelf standard and a single domino under the high end of the ramp. Position the dominoes so that the last .5 cm of the ramp extends beyond the point where the ramp contacts the domino,.and do the same in all subsequent setups.
Set the bracket on the table, touching the lower end of the ramp so that a ball rolling down the ramp will strike the bracket..
Mark a point about 3 cm below the top end of the ramp. Place a domino on the ramp to its high end is at this point, and place the ball just above the domino, so the domino is holding it back. Quickly pull the domino away from the ball so the ball begins to roll freely down the ramp. Allow the ball to roll until it strikes the bracket.
The bracket will probably move a little bit. Reset it at the end of the ramp.
Determine how far the ball rolled from release until it struck the bracket.
Now repeat, but this time use the TIMER. The first click will occur at the instant you release the ball, the second at the instant the ball strikes the bracket. Practice until you are as sure as you can be that you are clicking and pulling back the domino at the same instant, and that your second click is simultaneous with the ball striking the bracket.
When you are ready, do 5 trials 'for real' and record your time intervals.
Then reverse the system--without otherwise changing the position of the ramp, place the domino under the left end and position the bracket at the right end.
Time 5 trials with the ramp in this position.
In the space below, give the time interval for each trial, rounded to the nearest .001 second. Give 1 trial on each line, so that you will have a total of 10 lines, the first 5 lines for the first system, then 5 lines for the second system.
Beginning in 11th line give a short narrative description of what your data means and how it was collected.
Also describe what you were thinking, relevant to physics and the experiment, during the process of setting up the system and performing the trials.
Your answer (start in the next line):
L1 1.621 cm
L2 1.432 cm
L3 1.823 cm
L4 1.623 cm
L5 1.423 cm
R1 1.824 cm
R2 1.822 cm
R3 1.954 cm
R4 1.972 cm
R5 1.728 cm
The data represents the amount of time it took the ball to travel done the strap that was leveled by 1 domino. The data was
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Now place two dominoes under the right end and repeat the process, obtaining the time interval for each of 5 trials.
Then place the two dominoes under the left end and repeat once more.
Enter your 10 time intervals using the same format as before.
Your answer (start in the next line):
R1 1.123 sec
R2 1.224 sec
R3 1.093 sec
R4 1.005 sec
R5 1.126 sec
L1 0.845 sec
L2 0.822 sec
L3 0.954 sec
L4 0.911 sec
L5 0.854 sec
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Repeat the preceding using 3 dominoes instead of 2. Enter your 10 time intervals using the same format as before.
Your answer (start in the next line):
L1 0.604 sec
L2 0.782 sec
L3 0.554 sec
L4 0.684 sec
L5 0.698 sec
R1 0.822 sec
R2 0.812 sec
R3 0.831 sec
R4 0.783 sec
R5 0.872 sec
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Repeat the preceding again, still using the 3 domino setup, but this time place a CD or a DVD disk (or something of roughly similar thickness) on the 'low' end of the ramp. You need time only 5 intervals, but if you prefer you may use 10. Enter your 5 (or 10) time intervals using the same format as before.
Your answer (start in the next line):
0.877 sec
0.903 sec
0.743 sec
1.078 sec
0.825 sec
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Repeat the preceding one last time, still using the 3 domino setup, but remove the disk and replace it with a piece of paper. You need time only 5 intervals, but if you prefer you may use 10. Enter your 5 (or 10) time intervals using the same format as before.
Your answer (start in the next line):
0.844 sec
0.776 sec
0.734 sec
0.891 sec
0.765 sec
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Do your results support or fail to support the hypotheses you stated in the first two questions, regarding the relationship between time intervals and slopes? Explain.
Your answer (start in the next line):
I believe that my results supports my hypothesis because based on the data, the setups with the greater slope have the faster time intervals.
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How do you think the average velocity of the ball is related to the slope of the ramp? Explain in as much detail as possible.
Your answer (start in the next line):
I believe that the average velocity is related to the slope by the slope contributing to the amount of velocity the ball will have. If the slope is steep it’s more likely that velocity will increase and if the slope is not steep, the slower the ball will travel.
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Speculate on what it is that causes the average velocity on these ramps to change with slope.
Your answer (start in the next line):
The thing that cause of the average velocity on these to change the average velocity on these ramps to change with slope is the angle that the ball travels along the ramp.
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How might you verify whether your speculations are indeed valid explanations?
Your answer (start in the next line):
My hypothesis can be verify by the different angles of the ramp based on the number of dominos placed at one end of the ramp. It seems that the more dominos at the end of the ramp, the more steeper the ramp is and the faster the ball will travel.
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Do your data conclusively show that the disk made a difference?
Your answer (start in the next line):
My data barely shows that the disk made a significant difference with the speed of the ball travelling down the ramp. According to the data average of the two situations, the ramp with the disk is greater than the ramp without the disk but not as much, the difference of the two is .0612.
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Do your data conclusively show that the piece of paper made a difference?
Your answer (start in the next line):
My data do not show that the piece of paper made a difference.
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Imagine that someone is placing different objects below the 'low' end of the ramp, and you are timing the ball. Assume that somehow the object placed below the 'low' end is hidden from you in a way that does not interfere with the timing process. Compared to the thickness of the DVD, how thin would the object have to be before you would be unable, using the TIMER, to observe a difference in times down the ramp?
Answer this question in the first line below. Express your answer in multiples or fractions of the thickness of a disk.
Starting in the second line, explain how you came to your conclusion, based on the results you obtained in this experiment. Also discuss how you could modify or refine the experiment, still using the TIMER, to distinguish the effect of the thinnest possible object placed under the 'low end.
Your answer (start in the next line):
The amount of the thinness an object must have in order to not have the ability to observe a difference in the times down the ramp is ¼ of the disk.
I came up with my conclusion by comparing the size between the DVD disk and the paper, since the paper does not significantly change the amount of time a ball travelled on a leveled ramp. I believe the size of ¼ of a disk is flat enough to be similar to the size of the paper, in which it will affected the velocity of the ball while moving down a leveled ramp. If I could modify the experiment to distinguish the effect of the thinnest possible object placed under the low end, I would use a bunch of papers and will remove a sheet of paper after doing a trial until there is only one sheet of paper left.
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Had you placed the disk below the 'low' end of the ramp in a 1-domino setup, do you think the difference in times would have been greater or less? Do you think you would be better able distinguish the presence of a thinner object using the 1-domino setup, or the 3-domino setup? Explain your reasoning below:
Your answer (start in the next line):
I have to assume that a 1 domino setup would be better able to distinguish the presence of a thinner objet because the 1 domino setup is the least steepest and easier to manipulate the time interval.
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Does the ball's velocity change more or less quickly with the 3-domino setup or the 1-domino setup? Explain as best you can how you could use your results to support your answer.
Your answer (start in the next line):
The ball’s velocity change more quickly with the 3 domino setup because according the data I receive , the 3 domino setup produce faster laps than the 1 domino setup.
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*#&!
&#Your work on this lab exercise is good. Let me know if you have questions. &#