course Phy 202 r}BXfassignment #000
......!!!!!!!!...................................
20:12:12 Most queries in this course will ask you questions about class notes, readings, text problems and experiments. Since the first two assignments have been experiments, the first two queries are related to the experiments. While the remaining queries in this course are in question-answer format, the first two will be in the form of open-ended questions. Interpret these questions and answer them as best you can.
......!!!!!!!!...................................
RESPONSE --> ok
.................................................
......!!!!!!!!...................................
20:14:29 Different first-semester courses addressed the issues of experimental precision, experimental error, reporting of results and analysis in different ways and at different levels. One purpose of these initial lab exercises is to familiarize your instuctor with your work and you withthe instructor 's expectations. {}{}Comment on your experience with the three lab exercises you encountered in this assignment.
......!!!!!!!!...................................
RESPONSE --> I addressed the importance of precision and how to minimize errors in the first portion of my Physics I lab, so these exercises were similiar to those. It also helped me to familirize myself with the data program and the timer program which I assume will be used for later labs.
.................................................
......!!!!!!!!...................................
20:22:36 This question, related to the use of the TIMER program in an experimental situation, is posed in terms of a familiar first-semester system. Suppose you use a computer timer to time asteel ball 1 inch in diameter rolling down a straight wooden incline about 50 cm long. If the computer timer indicates that on five trials the times of an object down an incline are 2.42sec, 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 the following: {}{}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 positioning the object prior to release.{}{}e. Human uncertainty in observing exactly when the object reached the end of the incline.
......!!!!!!!!...................................
RESPONSE --> a. The discrepencies could be due to the lack of precision of the TIMER program. But we should always determine how precise an instrument is and consider that when we do calculations, so the errors can be minimized. b. Uncertain precision of human triggering is very likely. That's why it's important to take different trials and average the results. c.There could be actual differences in the time required to travel the same distance, but they should not deviate largely from the mean. If this happens, that trial should be repeated. d. This explanantion is similiar to human triggering in ""b"". Again, one should take great care to minimize systematic errors. e. Human uncertainty can be minimized by anticipating when the object will reach the end of the incline; this will generate more accurate results. confidence assessment: 3
.................................................
......!!!!!!!!...................................
20:26:58 How much uncertainty do you think each of the following would actually contribute to the uncertainty in timing a number of trials for the ball-down-an-incline lab? {}{}a. The lack ofprecision of the TIMER program{}{}b. The uncertain precision of human triggering (uncertainty associated with an actual human finger on a computer mouse){}{}c. Actual differencesin 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.
......!!!!!!!!...................................
RESPONSE --> I will rate my responses on a scale from 1-5, 5 being a large amount of uncertainty and 1 being the least amount of uncertainty a. 2-We can assess the precision of the TIMER program before we begin and consider it when calculating results. b.3-Human error can cause quite a bit of uncertainty. c.1-This number will only deviate slightly when all other errors are minimized fully. d.5- This can make a large deviation in results. e.3- This can be minimized by anticipating the exact moment when the object will reach the end of the incline. confidence assessment: 2
.................................................
......!!!!!!!!...................................
20:31:32 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 uncertainprecision 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 positioning the object prior to release.{}{}e. Humanuncertainty in observing exactly when the object reached the end of the incline.
......!!!!!!!!...................................
RESPONSE --> A: You can assess the precision of the instrument used before you do the experiment. Use this assessment when calculating your results. B. If possible have a lab partner and do two different sets of trials with two different people controlling the trigger and assess the results. If more than one person is not available, then you can pay close attention, but not much else can be done. C. Averaging results will give a more accurate calculation for the time required to travel the same distance. D: Mark the position with a marker or piece of tape and use a ruler to line the ball exactely with the marker before release. E Anticipate when the ball will reach the end of the incline. Therefore, your time will not be too late or too early. confidence assessment: 3
.................................................
ҙ٣yvn assignment #000 000. Physics II 06-11-2007"