phy201
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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cq_1_091
phy201
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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seed 9.1
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: ->->->->->->->->->->->-> : ->->->->->->->->->->->-> :
'ds= 20cm
v0=0
'dt=2
'ds=(v0+vf)/2 * 'dt
20cm=(0cm/s+vf)/2 * 2s
40cm=0cm/s +vf *2s
40cm/2s-0cm/s=vf
vf=20cm/s
a='dv/'dt
a= 20cm/s/2s = 10cm/s^2
vave= (20cm/s + 0cm/s)/2 = 10cm/s
#$&*
If the time interval is in error so that it is 3% longer than the actual time interval, then what are the
actual values of the final velocity and acceleration?
answer/question/discussion: ->->->->->->->->->->->-> : ->->->->->->->->->->->-> :
3% increase of 2seconds = .03 * 2= 1.94seconds
vf=40cm/1.94s
vf=20.61cm/s
a=20cm/s/1.94s = 10.31cm/s^2
Your `dv would be based on the initial velocity (zero) and the final velocity (which you calculated correctly to be 20.61 cm/s.
#$&*
What is the percent error in each?
answer/question/discussion: ->->->->->->->->->->->-> : ->->->->->->->->->->->-> :
vf= 20cm/s/20.61cm/s
97 percent
a= 10cm/s^2 / 10.31cm/s^2
97 percent
#$&*
If the percent error is the same for both velocity and acceleration, explain why this must be so.
answer/question/discussion: ->->->->->->->->->->->-> : ->->->->->->->->->->->-> :
The percent error is the same for both velocity and acceleration because they are both calculated by the
same time interval even though they are independent of each other they are both dependent on the amount of
time that it for an object to travel.
????????I am still a little confused aboutt he percent error for the acceleration, should I have calulated the change in velocity with the 3 percent error first and then divided that by the change in time to get the 6% error??? I was confused on the soltion for this??
#$&*
If the percent errors are different explain why it must be so.
answer/question/discussion: ->->->->->->->->->->->-> : ->->->->->->->->->->->-> :
#$&*
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30 minutes
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You won't have any trouble understanding the discussion at the link below. If you do have questions or aren't completely sure, you're welcome to submit a revision.
&#Please compare your 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. &#
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This is the revision...or question I has about this assignment.
I can't locate your insertions in this document.