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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.
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What are its average velocity, final velocity and acceleration?
answer/question/discussion: ->->->->->->->->->->->-> scussion:
vo= 0cm/s `ds= 2sec `dt= 20cm 20cm/2sec= 10cm/s vAve 10cm/s*2= 20cm/s vf (20cm/s-0cm/s)/2sec= 10cm/s/s accell
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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: ->->->->->->->->->->->-> scussion:
0.3 * 2sec= 0.6sec making the actual 2-0.6= 1.4sec
20cm/1.4sec= 14.3cm/s * 2 = vf= 28.6cm/s (28.6cm/s-0cm/s)/2sec= 14.3cm/s/s
@& Your last calculation assumes a time interval of 2 s. Your new time interval is 1.4 sec, not 2 sec..
However note also that 3% is .03, not .3.*@
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What is the percent error in each?
answer/question/discussion: ->->->->->->->->->->->-> scussion:
(20-28.6)/28.6 *100= 30% error for vf
(10-14.3)/14.3 *100= 30% error for a
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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: ->->->->->->->->->->->-> scussion:
because the acceleration was constant
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If the percent errors are different explain why it must be so.
answer/question/discussion: ->->->->->->->->->->->-> scussion:
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15 minutes
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@& See my note. You'll need to recalculate your results based on a 3% uncertaintly rather than the 30% you used.
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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. &#
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