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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):
I would guess that the balls average velocity is 7 cm/sec. I find this value by adding the two given values together and then dividing them by two.
4 cm/sec + 10 cm/sec = 14 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 further information, the 7 cm/sec is just a guess because we have no idea if the change in velocity was constant. For example the ball may have traveled at 4 cm/sec for almost the entire length and then rapidly speed up causing a higher average velocity at the end.
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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):
To try and find out how far the ball traveled in the time given we should multiply the time taken by the average velocity. This would give us a distance of 21 cm. We can find this with the following equation:
7 cm/sec * 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):
The average rate that the ball's velocity changed with respect to clock time during this interval was 2 cm/sec. This can be found by first of all finding the difference between the starting average velocity and the ending average velocity.
To do this we do 10 cm/sec - 4 cm/sec = 6 cm/sec. Now that we have the change in average velocity, we can divide it by the change in time, 3 seconds.
6 cm/sec / 3 sec = 2 cm/sec/sec.
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15 minutes
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2/28 11:10
&#Your work looks very good. Let me know if you have any questions. &#