Phy 201
Your 'cq_1_03.1' 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 0 and accelerates down a ramp of length 30 cm, covering the distance in 5 seconds.
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What is its average velocity?
answer/question/discussion: 6 cm/s
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If the acceleration of the ball is uniform then its average velocity is equal to the average of its initial and final velocities.
answer/question/discussion: right
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You know its average velocity, and you know the initial velocity is zero. What therefore must be the final velocity?
answer/question/discussion: 6 cm/s
What is the initial velocity?
What is the final velocity?
What is the average velocity?
Is the average velocity you just gave the equal to the average of the initial and final velocities, as you gave them?
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By how much did its velocity therefore change?
answer/question/discussion: 6 cm/s from initial velocity (zero)
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What is the initial velocity?
What is the final velocity?
What therefore is the change in velocity?
What is the definition of the rate at which velocity changes with respect to clock time?
What is the change in velocity?
What is the change in clock time?
What therefore is the rate of change of velocity with respect to clock time?
At what average rate did its velocity change with respect to clock time?
answer/question/discussion: 1.2 cm/s
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What would a graph of its velocity vs. clock time look like? Give the best description you can.
answer/question/discussion: a straight line slanting up and to the right starting at zero and increasing 1.2 cm for every 1 second
What point on your graph corresponds to the beginning of the interval? (give both the t coordinate and the v coordinate of the point on a graph of v vs. t)
What point corresponds to the end of the interval?
What is the rise between your two points?
What is the run between your two points?
What therefore is the slope of your graph between the two points?
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15 minutes
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You have most of the right ideas. However you have at least one fundamental error (perhaps only one), which affects most of your answers, and you need to correct it.
Please see my notes and submit a copy of this document with revisions and/or questions, and mark your insertions with &&&&.