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Phy 121
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):
( 10 cm + 4 cm)/(1 second + 1 second)
14 cm/2 second
7 cm/second
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• Without further information, why is this just a guess?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
We are only provided with the beginning and end times. We do not know if the velocity was greater or less than the average during the start and finish.
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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):
Since we know that the average velocity is 7 cm/second, we can determine how far it traveled in 3 seconds: (7cm/second) * 3 seconds = 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):
(21 cm – 7cm)/(3 seconds – 1 seconds)
14 cm/2 seconds
7 cm/second
21 cm is a displacement.
7 cm/s is average velocity.
There is no quantity associated with this interval which is equal to 7 seconds.
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Unknown
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Very good, but you have repeated an earlier error in calculating the acceleration. You should submit a revision to be sure you understand that calculation and the nature of your error.
&#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. &#