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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):
10cm/sec + 4cm/sec = 14 cm/sec
14cm/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):
Because you do not know if it was a constant acceleration or not.
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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):
vAve = ‘ds / ‘dt
7cm/sec = ‘ds / 3sec
7 cm/sec * 3sec = ‘ds
‘ds = 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):
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Average rate = change in velocity / change in time
Average rate = 10cm/sec - 4cm/sec / 3sec
Average rate = 6cm/sec / 3sec
Average rate = 2 cm/sec^2
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15 minutes
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9/30/11 8:50pm
&#Very good responses. Let me know if you have questions. &#