Phy231
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 uniformly down a ramp of length 30 cm, covering the distance in 5 seconds.
What is its average velocity?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
30cm/5sec= 6cm/sec
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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.
You know its average velocity, and you know the initial velocity is zero.
What therefore must be the final velocity?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
0 +10=10/2=5 So it's final velocity was 10cm/sec
You haven't put units on your quantities and I'm not sure where your first 10 came from; however I'm pretty sure you've misidentified some of your information. This result doesn't follow from the preceding information.
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By how much did its velocity therefore change?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
10cm/sec/5sec=2cm So it increases ana average of 2cm/sec
your units aren't correct; the 10 cm/s isn't correct either, though your overall strategy for solving this is sound
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At what average rate did its velocity change with respect to clock time?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
See previous answer....
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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: ->->->->->->->->->->->-> (start in the next line):
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It would be a straight line in the first quadrant going from bottom left to upper right. It would have a slope of 6.
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15min
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2/11/10 11am
&#Please compare your solutions with the expanded discussion at the link
Solution
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