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phy 201
Your 'cq_1_09.1' 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 accelerates uniformly as it rolls 20 cm down a ramp, starting from rest, in 2 seconds.
• What are its average velocity, final velocity and acceleration?
answer/question/discussion: ->->->->->->->->->->->-> :
average velocity: 20cm/2s = 10cm/s
final velocity: 0 m/s? - not sure how to get that. Initial velocity is 0 cm/s too? Or 10cm/s
Vave = (final velocity - initial velocity) / 2 =
(final velocity -0) / 2 = 10 cm/s
Final velocity = 20cm/s
acceleration: 10cm/s/ 2s= 5 cm/s^2
@& What is the ball's initial velocity on this interval?
What is its final velocity on the interval?
What therefore is its change in velocity? (it's not 10 cm/; be sure you understand why).
What therefore is its acceleration?*@
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• If the time interval is in error so that it is 3% longer than the actual time interval, then what are the actual values of the final velocity and acceleration?
answer/question/discussion: ->->->->->->->->->->->-> :
average velocity: 20cm/2s = 10cm/s x 1.03 = 10.3 cm/s
@& If the ball takes 3% longer, its final velocity will be less than it was before.*@
final velocity: 20cm/s x 1.03 = 20.6
acceleration: 10cm/s/ 2s= 5 cm/s^2 x 1.03= 5.15 cm/s^2
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• What is the percent error in each?
answer/question/discussion: ->->->->->->->->->->->-> :
3% error for all
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• If the percent error is the same for both velocity and acceleration, explain why this must be so.
answer/question/discussion: ->->->->->->->->->->->-> :
Because velocity and acceleration are dependent on time
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• If the percent errors are different explain why it must be so.
answer/question/discussion: ->->->->->->->->->->->-> :
percent error shouldn’t be different because all are dependent on time
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20 min
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I keep getting my concepts confused. Should I refer to the textbook or your notes?
self-critique #$&*
#$&* self-critique
self-critique rating
rating #$&*:
&#See any notes I might have inserted into your document, and before looking at the link below see if you can modify your solutions. If there are no notes, this does not mean that your solution is completely correct.
Then please compare your old and new solutions with the expanded discussion at the link
Solution
Self-critique your solutions, if this is necessary, according to the usual criteria. Insert any revisions, questions, etc. into a copy of this posted document. Mark any insertions with &&&& so they can be easily identified.If your solution is completely consistent with the given solution, you need do nothing further with this problem. &#
@& You're on the right track but you're missing a couple of details.
&#Please see my notes and, unless my notes indicate that revision is optional, submit a copy of this document with revisions and/or questions, and mark your insertions with &&&& (please mark each insertion at the beginning and at the end).
Be sure to include the entire document, including my notes.
If my notes indicate that revision is optional, use your own judgement as to whether a revision will benefit you. &#
*@