cq_1_091

#$&*

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= change displacement/change time= 20cm/2seconds= 10cm/s

final velocity is 2*10cm/s since the initial velocity is equal to zero

final velocity= 20cm/s

acceleration= change velocity/change time=(20cm/s)/2seconds= 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: ->->->->->->->->->->->-> :

final velocity= 19.4cm/s

acceleration= 9.4cm/s^2

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What is the percent error in each?

answer/question/discussion: ->->->->->->->->->->->-> :

percent error= (actual-calculated/actual)*100

20cm/s-19.4cm/s/20cm/s*100= 1.5% error for final velocity

@& right, but that's a 3% error*@

error for acceleration= 6% error

@& very good*@

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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: ->->->->->->->->->->->-> :

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If the percent errors are different explain why it must be so.

answer/question/discussion: ->->->->->->->->->->->-> :

The percent errors are different because the error is being applied mulitple times, in the calculation for velocity and acceleration.

#$&*

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15 min

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@& Very good.

Keep up the good work.*@