cq_1_041

Phy 231

Your 'cq_1_04.1' 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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A ball is moving at 10 cm/s when clock time is 4 seconds, and at 40 cm/s when clock time is 9 seconds.

• Sketch a v vs. t graph and represent these two events by the points (4 sec, 10 cm/s) and (9 s, 40 cm/s).

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

With the given two points, the graph just looks linear and it is increasing at a constant rate.

The rise is 40 cm/s – 10 cm/s = 30 cm/s, The run is 9s – 4 s = 5 s. The slope can then be found by 30 cm/s / 5 s = 6 cm/s/s. The graph has a slope of 6 cm/s/s.

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• Sketch a straight line segment between these points.

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

The line gives a better view at how the line is linear and increasing at a constant rate.

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• What are the rise, run and slope of this segment?

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

The rise is 40 cm/s – 10 cm/s = 30 cm/s, The run is 9s – 4 s = 5 s. The slope can then be found by 30 cm/s / 5 s = 6 cm/s/s. The graph has a slope of 6 cm/s/s.

Good.

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• What is the area of the graph beneath this segment?

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

The area of the graph beneath the segment is the same as the total distance traveled. I found that it was 180 cm. 40 cm/s / 2 = 20 cm/s and then the total time is 9 sec, so 20 cm/s * 9 s = 180 cm.

Good explanation, but your result isn't correct.

The time interval lasts only 5 seconds.

The initial velocity isn't 0 so the average velocity isn't half the final velocity.

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15 mins

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Solution

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