Your 'cq_1_05.1' 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 accelerates at 8 cm/s^2 for 3 seconds, starting with velocity 12 cm/s.
· What will be its velocity after the 3 seconds has elapsed?
answer/question/discussion: starting velocity + the rate of acceleration for 3 seconds = 12cm/s = 24cm/s = 36cm/s
· Assuming that acceleration is constant, what will be its average velocity during this interval?
answer/question/discussion: During this 3 second interval, the ball’s velocity changed from 12 cm/s to 36cm/s. The final velocity – the initial velocity divided by 2 (to average obviously) would be (36cm/s – 12cm/s) / 2 = 12cm/s
you average two number by adding them and dividing by 2, not subtracting and dividing by 2.
How does this change your answer?
· How far will it travel during this interval?
answer/question/discussion: At an average rate of 12cm/s for 3 seconds the ball will travel 36cm.
The ball starts out at 12 cm/s and speeds up. Its average velocity will clearly be greater than 12 cm/s (see also above note).
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10 min
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Good work except for one error. See my notes.
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