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Phy 241
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: ->->->->->->->->->->->-> :
vAve= 20cm/2s = 10cm/s
vf=10cm/s*2-0cm/s = 20cm/s
a=20cm/s / 2s = 10cm/s^2
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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 = 1.94
vAve = 20cm/1.94s = 10.31cm/s
vf=10.31cm/s*2-0cm/s = 20.62cm/s
a=20.62cm/s / 1.94s = 10.63cm/s^2
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• What is the percent error in each?
answer/question/discussion: ->->->->->->->->->->->-> :
%vf = (20.62 - 20)/20 * 100 = 3.1%
%a = (10.63 - 10)/10 * 100 = 6.3%
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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: ->->->->->->->->->->->-> :
The % error for the velocity is roughly the same because the error in time is only involved one time.
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• If the percent errors are different explain why it must be so.
answer/question/discussion: ->->->->->->->->->->->-> :
The percent error for acceleration is higher because the 3% error in time is involved in finding both the velocity and the acceleration.
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&#Very good responses. Let me know if you have questions. &#