course Phy 231 ¬ŽÏÇ Ü‡bص|Û¼Ô}°šëCÀ䙞¢assignment #000
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19:49:49 The Query program normally asks you questions about assigned problems and class notes, in question-answer-self-critique format. Since Assignments 0 and 1 consist mostly of lab-related activities, most of the questions on these queries will be related to your labs and will be in open-ended in form, without given solutions, and will not require self-critique. The purpose of this Query is to gauge your understanding of some basic ideas about motion and timing, and some procedures to be used throughout the course in analyzing our observations. Answer these questions to the best of your ability. If you encounter difficulties, the instructor's response to this first Query will be designed to help you clarify anything you don't understand. {}{}Respond by stating the purpose of this first Query, as you currently understand it.
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RESPONSE --> The purpose of this first query is to gauge my understanding of the basic ideas about motion, timing, and procedures used in the course.
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19:51:59 If, as in the object-down-an-incline experiment, you know the distance an object rolls down an incline and the time required, explain how you will use this information to find the object 's average speed on the incline.
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RESPONSE --> The object's average speed on the incline can be found by dividing the distance that it traveled on the incline by the time required to travel that distance. confidence assessment: 3
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20:01:06 If an object travels 40 centimeters down an incline in 5 seconds then what is its average velocity on the incline? Explain how your answer is connected to your experience.
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RESPONSE --> The average velocity of the object is found by dividing the distance, in this case 40cm, by the time required to travel that distance, in this case 5s. 40cm/5s = 8cm/s In my results of a can moving down an incline, the average velocity was from a distance of 26cm/2.417s ~ 11cm/s. confidence assessment: 3
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20:08:41 If the same object requires 3 second to reach the halfway point, what is its average velocity on the first half of the incline and what is its average velocity on the second half?
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RESPONSE --> For an object traveling down the 40cm incline in 5s: The object traveling down the first half of the incline would have an average velocity of 20cm/3s ~ 6.66cm/s Over the second half, the object would have an average velocity of 20cm/2s = 10cm/s confidence assessment: 3
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20:31:49 Using the same type of setup you used for the first object-down-an-incline lab, if the computer timer indicates that on five trials the times of an object down an incline are 2.42 sec, 2.56 sec, 2.38 sec, 2.47 sec and 2.31 sec, then to what extent do you think the discrepancies could be explained by each of thefollowing: {}{}a. The lack of precision of the TIMER program{}{}b. The uncertain precision of human triggering (uncertainty associated with an actual human finger on a computer mouse){}{}c. Actual differences in the time required for the object to travel the same distance.{}{}d. Differences in positioningthe object prior to release.{}{}e. Human uncertainty in observing exactly when the object reached the end of the incline.
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RESPONSE --> a. The timer is pretty precise for the needs of this measurement. b. There is a possibility for error here c. I would not expect any change here. d. These might make a small difference, but I would imagine not by much assuming that care was taken to start from the same point each time e. I would imagine that this could be the most important potential for error. A person could anticipate the object reaching the end of the confidence assessment: 3
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20:38:12 How much uncertainty do you think each of the following would actually contribute to the uncertainty in timing a number of trials for the object-down-an-incline lab? {}{}a. The lack of precision of the TIMER program{}{}b. The uncertain precision of human triggering (uncertainty associated bLine$(lineCount) =with an actual human finger on a computer mouse){}{}c. Actual differences in the time required for the object to travel the same distance.{}{}d. Differences in positioning the object prior to release.{}{}e. Human uncertainty in observing exactly when the object reached the end of the incline.
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RESPONSE --> a. The timer seems to be accurate to 3 decimal places, and as we saw earlier, only when used in extremely short intervals do we see problems with the times. b. I think that for most people, there should be no problems with the precision of mouse skills c. I think that there should be no difference for uncertainty here d. this may contribute to some uncertainty e.This may contribute to the uncertainty due to the method used to determine when to click. confidence assessment: 3
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20:44:42 What, if anything, could you do about the uncertainty due to each of the following? Address each specifically. {}{}a. The lack of precision of the TIMER program{}{}b. The uncertain precision of human triggering (uncertainty associated with an actual human finger on a computer mouse){}{}c. Actualdifferences in the time required for the object to travel the same distance.{}{}d. Differences in positioning the object prior to release.{}{}e. Human uncertainty in observing exactly when the object reached the end of the incline.
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RESPONSE --> a. The software would have to be modified to be more precise. b. There is not much to improve upon triggering the mouse. c. If there were actual differences, then there may be something inhibiting the movement of the object. d. Mark precisely where to start the object. e. Use audio cues rather than visual cues to trigger the click of the mouse in order to prevent prediction of when the object will reach the end. confidence assessment: 3
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20:52:09 According to the results of your introductory pendulum experiment, do you think doubling the length of the pendulum will result in half the frequency (frequency can be thought of as the number of cycles per minute), more than half or less than half?
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RESPONSE --> No, I do not think that doubling the length of the pendulum would result in half the frequency. It would have more than half the number of cycles of the original pendulum length. confidence assessment: 3
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20:58:22 Note that for a graph of y vs. x, a point on the x axis has y coordinate zero and a point on the y axis has x coordinate zero. In your own words explain why this is so.
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RESPONSE --> The point on the x-axis has a y coordinate of zero because if it had a y-coordinate of any other number it would not be on the x-axis. The same is true for the y-axis. If the x-coordinate were anything other than 0, it would not be on the y-axis. The axes are defined as the line where x=0 for the y-axis and the line where y=0 for the x-axis. confidence assessment: 3
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21:06:23 On a graph of frequency vs. pendulum length (where frequency is on the vertical axis and length on the horizontal), what would it mean for the graph to intersect the vertical axis (i.e., what would it mean, in terms of the pendulum and its behavior, if the line or curve representing frequency vs. length goes through the vertical axis)? What would this tell you about the length and frequency of the pendulum?
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RESPONSE --> An intersection of the vertical axis would indicate a length of 0 on the pendulum. If the pendulum had no length, how could it have a frequency? confidence assessment: 3
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21:09:43 On a graph of frequency vs. pendulum length, what would it mean for the graph to intersect the horizontal axis (i.e., what would it mean, in terms of the pendulum and its behavior, if the line or curve representing frequency vs. length goes through the horizontal axis)? What would this tell you about the length and frequency of the pendulum?
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RESPONSE --> If the graph intersected the horizontal axis, this would mean that the frequency would be zero. This would mean the pendulum did not complete a cycle at that the length at which it crossed the horizontal axis. confidence assessment: 3
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21:11:52 If a ball rolls down between two points with an average velocity of 6 cm / sec, and if it takes 5 sec between the points, then how far apart are the points?
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RESPONSE --> To find the distance, we multiply the average velocity and multiply it by the change in time: 6cm/s * 5s = 30cm The points are 30cm apart. confidence assessment: 3
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21:12:32 On the average the ball moves 6 centimeters every second, so in 5 seconds it will move 30 cm. {}{}The formal calculation goes like this: {}{}We know that vAve = `ds / `dt, where vAve is ave velocity, `ds is displacement and `dt is the time interval. {}It follows by algebraic rearrangement that `ds = vAve * `dt.{}We are told that vAve = 6 cm / sec and `dt = 5 sec. It therefore follows that{}{}`ds = 6 cm / sec * 5 sec = 30 (cm / sec) * sec = 30 cm.{}{}The details of the algebraic rearrangement are asfollows:{}{}vAve = `ds / `dt. We multiply both sides of the equation by `dt:{}vAve * `dt = `ds / `dt * `dt. We simplify to obtain{}vAve * `dt = `ds, which we then write as{}`ds = vAve *`dt.{}{}Be sure to address anything you do not fully understand in your self-critique.
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RESPONSE --> self critique assessment: 3
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20:38:46 You were asked to read the text and some of the problems at the end of the section. Tell me about something in the text you understood up to a point but didn't understand fully. Explain what you did understand, and ask the best question you can about what you didn't understand.
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RESPONSE --> I actually think that I understood what was being said in the text, but I do think that I will have to work some of the excercises to be sure that I know how to use them properly when solving problems. I tried the examples as I was reading to see if I understood or had any idea how to solve it before reading the answer with mixed results. I believe it will just take some practice. confidence assessment: 3
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22:07:03 Tell me about something in the problems you understand up to a point but don't fully understand. Explain what you did understand, and ask the best question you can about what you didn't understand.
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RESPONSE --> I have read over the questions and have worked through over half of them and checking the odd ones, I feel like I am on the right track. confidence assessment: 3
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