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course Phy 202

ph2 query 0Most queries in this course will ask you questions about class notes, readings, text problems and experiments. Since the first two assignments have been lab-related, the first two queries are related to the those exercises. 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.

Different first-semester courses address 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 instructor with your work and you with the instructor 's expectations.

Comment on your experience with the three lab exercises you encountered in this assignment or in recent assignments.

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Question: 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 a steel 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:

• The lack of precision of the TIMER program.

To what extent to you think the discrepancies are explained by this factor?

your answer: vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv

The program could possibly glitch and go faster or slower than what it is supposed to

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• The uncertain precision of human triggering (uncertainty associated with an actual human finger on a computer mouse)

To what extent to you think the discrepancies are explained by this factor?

your answer: vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv

The times could be exactly the same but because of the human error the timer isn’t being stopped at the correct times so the times are different

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• Actual differences in the time required for the object to travel the same distance.

To what extent to you think the discrepancies are explained by this factor?

your answer: vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv

there could be different slopes in the path making the times slower and faster

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• Differences in positioning the object prior to release.

To what extent to you think the discrepancies are explained by this factor?

your answer: vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv

If the objects aren’t dropped in the same spot then they may have other factors interfering with the path of travel

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• Human uncertainty in observing exactly when the object reached the end of the incline.

To what extent to you think the discrepancies are explained by this factor?

your answer: vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv

The human uncertainty no being able to judge when the object reaches the end so the human wouldn’t stop the program in time

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Question: 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?

• The lack of precision of the TIMER program.

To what extent to you think this factor would contribute to the uncertainty?

your answer: vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv

This lake of precision in the program contribute very little in the uncertainty due to the fact that all the times would be run on the same program and under the same timing speeds

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• The uncertain precision of human triggering (uncertainty associated with an actual human finger on a computer mouse)

To what extent to you think this factor would contribute to the uncertainty?

your answer: vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv

This would contribute under a second of difference in the uncertainty depending upon the reaction timing of the human

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• Actual differences in the time required for the object to travel the same distance.

To what extent to you think this factor would contribute to the uncertainty?

your answer: vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv

This could contribute a great deal to the uncertainty factor depending on the cause of diffence in timing. It could be something so small as to be a fluke, but if the timing was drastically different causing a great amount of uncertainty as in why it was happening.

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• Differences in positioning the object prior to release.

To what extent to you think this factor would contribute to the uncertainty?

your answer: vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv

This could cause a great deal of uncertainty cause there could be a great deal of difference in the slopes of the paths the object is traveling causing it to be greatly discrepancy in speed

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• Human uncertainty in observing exactly when the object reached the end of the incline.

To what extent to you think this factor would contribute to the uncertainty?

your answer: vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv

A human reaction time can be slower than normal or faster giving the a great uncertainty range

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Question: What, if anything, could you do about the uncertainty due to each of the following? Address each specifically.

• The lack of precision of the TIMER program.

What do you think you could do about the uncertainty due to this factor?

your answer: vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv

You could reset the program

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• The uncertain precision of human triggering (uncertainty associated with an actual human finger on a computer mouse)

What do you think you could do about the uncertainty due to this factor?

your answer: vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv

Have the human as alert as possible and have them react as uniformly as possible to the object beginning and ending

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• Actual differences in the time required for the object to travel the same distance.

What do you think you could do about the uncertainty due to this factor?

your answer: vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv

Record the different times and take into account the differences may be due to human error and if they are extremely different mark them as outliers

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• Differences in positioning the object prior to release.

What do you think you could do about the uncertainty due to this factor?

your answer: vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv

Try to position the objects as closely together as possible and maybe mark the position of where you are dropping them to keep them close together

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• Human uncertainty in observing exactly when the object reached the end of the incline.

What do you think you could do about the uncertainty due to this factor?

your answer: vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv

Have the human be as alret as possible and also have them judging the objects passing two points one for the beginning and the end

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&#Your work looks good. Let me know if you have any questions. &#