cq_1_022

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PHY 201

Your 'cq_1_02.2' 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_02.2_labelMessages **

The problem:

A graph is constructed representing velocity vs. clock time for the interval between clock times t

= 5 seconds and t = 13 seconds. The graph consists of a straight line from the point (5 sec, 16

cm/s) to the point (13 sec, 40 cm/s).

What is the clock time at the midpoint of this interval?

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

M= [(x1+ x2)/2] , [(y1 + y2)/2] = [(5+13)/2], [(16cm/s + 40cm/s)/2] = (9 sec, 28cm/s)

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What is the velocity at the midpoint of this interval?

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

Since the graph is velocity vs. clock time, 28cm/s is the velocity at the midpoint interval.

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How far do you think the object travels during this interval?

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

`ds = vAve * `dt = 28cm/s * (13sec-5sec) = 28cm/s * 8 sec = 224cm * sec /sec = 224cm

`ds =224cm

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By how much does the clock time change during this interval?

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

13 sec - 5 sec = 8 seconds

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By how much does velocity change during this interval?

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

40cm/s - 16cm/s = 24 cm/sec

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What is the average rate of change of velocity with respect to clock time on this interval?

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

aAve = 24cm/s / 8 sec = 3cm/s /second

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What is the rise of the graph between these points?

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

The rise = 'dv, so 24 units. 40 -16 =24

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What is the run of the graph between these points?

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

Run = 'dt, so 8 units. 13 - 5 = 8 units

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What is the slope of the graph between these points?

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

m = rise/run, so m=24/8 or m=3.

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@&

Rise, run and slope all have units, which in this case are consistent with the corresponding units of your previous calculations.

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What does the slope of the graph tell you about the motion of the object during this interval?

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

The slope of the graph tells me that the object is increasing the distance it travels in cm/sec for

each second that passes.

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What is the average rate of change of the object's velocity with respect to clock time during this

interval?

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

24cm/sec / 8sec = 3cm/sec/sec

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*#&!

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