course Phy 121
13/Jul/2010 21:43
The problem: 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.
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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):
Graph is increasing at an increasing rate. Rise = 30, Run = 5. Slope is positive. Line is moving Left-to right
The graph is increasing, but there is no information about whether it is increasing at a constant, increasing or decreasing rate. If the graph is a straight line it's increasing at a constant rate, but as already stated we don't know this to be the case.
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Sketch a straight line segment between these points.
answer/question/discussion (start in the next line):
Graph is increasing at an increasing rate. Rise = 30, Run = 5. Slope is positive. Line is moving Left-to right
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What are the rise, run and slope of this segment?
answer/question/discussion (start in the next line):
Graph is increasing at an increasing rate. Rise = 30, Run = 5. Slope is positive. Line is moving Left-to right
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What is the area of the graph beneath this segment?
answer/question/discussion (start in the next line):
Area = .5 * base * height = .5 * (5 * 30) = 75\
the region is a trapezoid, not a triangle.
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Copy and paste your work into the box below and submit as indicated:
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5 min"
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Solution
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