cq_1_021

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PHY 241

Your 'cq_1_02.1' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.

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The problem:

A ball starts with velocity 4 cm/sec and ends with a velocity of 10 cm/sec.

• What is your best guess about the ball's average velocity?

answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):

It is between 4cm/sec and 10cm/sec

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• Without further information, why is this just a guess?

answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):

You need to know how long it traveled for to reach 10cm/sec to get an average.

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• If it takes 3 seconds to get from the first velocity to the second, then what is your best guess about how far it traveled during that time?

answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):

Well it had to travel at least 12 cm.

@& If it never slows then it has to go at least 12 cm.

Assuming uniform acceleration the displacement would be 21 cm.*@

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• At what average rate did its velocity change with respect to clock time during this interval?

answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):

2cm/sec

@& The units of (cm/s) / s are cm/s^2, not cm/s.*@

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&#See any notes I might have inserted into your document, and before looking at the link below see if you can modify your solutions. If there are no notes, this does not mean that your solution is completely correct.

Then please compare your old and new solutions with the expanded discussion at the link

Solution

Self-critique your solutions, if this is necessary, according to the usual criteria. Insert any revisions, questions, etc. into a copy of this posted document. Mark any insertions with &&&& so they can be easily identified.

If your solution is completely consistent with the given solution, you need do nothing further with this problem. &#

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