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.

** CQ_1_02.1_labelMessages.txt **

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: ->->->->->->->->->->->-> scussion (start in the next line):

To get an average you add all the answers together and then divide by the number of answers you added. 10 cm/sec + 4 cm/sec = 14 cm/sec divide by 2 = 7 cm/sec is the average.

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Without further information, why is this just a guess?

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

We are only given two velocities, start and end. The ball could have spent more time at the higher velocity/lower velocity and the average would be higher/lower. The ball could have exceeded either velocity, also changing the 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: ->->->->->->->->->->->-> scussion (start in the next line):

avg velocity = delta position/ delta clock time

delta position = avg velocity * delta clock time

? = 7cm/sec * 3 sec

? = 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: ->->->->->->->->->->->-> scussion (start in the next line):

10 cm/sec - 4 cm/sec = 6 cm/sec

[6 cm/sec] / 3 seconds = 2 cm/sec^2

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10 min

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&#Very good responses. Let me know if you have questions. &#