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Phy 121
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.
** CQ_1_09.1_labelMessages **
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
‘dt=2s
v0=0cm/s
vAve=20cm/2s=10cm/s
vf=10cm/s*2=20cm/s
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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: ->->->->->->->->->->->-> :
‘dt=2s*.03=.06s+2s=2.06s
vAve=20cm/s/2.06s=9.71cm/s
vf=9.71cm/s*2=19.42cm/s
a=19.42cm/s/2.06s=9.43cm/s^2
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• What is the percent error in each?
answer/question/discussion: ->->->->->->->->->->->-> :
There is about 3% error for both vAve and vf
So that means it is a 6% error for acceleration
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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: ->->->->->->->->->->->-> :
If both velocity and acceleration have the same error percentage means that the velocity and acceleration values would have to be the same.
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• If the percent errors are different explain why it must be so.
answer/question/discussion: ->->->->->->->->->->->-> :
They are different because both the velocity and time have a 3% error and the acceleration used both of them to find acceleration so that means acceleration has a 6% error.
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30 min
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&#Very good responses. Let me know if you have questions. &#