Phy 201
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):
(4 cm/sec + 10 cm/sec) / 2 = 7 cm/sec
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• Without further information, why is this just a guess?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
Without knowing the changes in distance and time, all we can do is average the two given velocities.
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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):
(7 cm/sec) / 3 = 2.333 cm/sec
1st second = 4 cm
2nd second = 6.333 cm
3rd second = 8.666 cm
4 cm + 6.333 cm + 8.666 cm = 18.999 cm or 19 cm
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Not a bad estimate, and your answer shows good insight. However your result for each second is based on the velocity at the beginning of that 1-second interval; the velocity is presumably increasing on each interval so your result is an underestimate.
• At what average rate did its velocity change with respect to clock time during this interval?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
( 7 cm/sec) / 3 sec = 2.333 cm/sec / sec
you should be dividing change in velocity by change in clock time
you have apparently divided average velocity by change in clock time
Right idea, but missing some details.
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10 minutes
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&#Please compare your 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. &#