cq_1_071

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phy 201

Your 'cq_1_07.1' 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_07.1_labelMessages **

A ball falls freely from rest at a height of 2 meters.  Observations indicate that the ball reaches the ground in .64 seconds. 

• Based on this information what is its acceleration?

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

vAve=ds/dt

vAve=2/.64=3.125

vf=vAve*2

vf=3.125*2=6.25

aAve=vf/dt

aAve=6.25/.64=9.76

aAve=9.8

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• Is this consistent with an observation which concludes that a ball dropped from a height of 5 meters reaches the ground in 1.05 seconds?

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

vAve=5/1.05=4.76

vf=4.76*2=9.52

aAve=9.52/1.05=9.07

aAve=9.1

This is not consistent with the previous equation.

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• Are these observations consistent with the accepted value of the acceleration of gravity, which is 9.8 m / s^2?

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

 The first equation is almost on the money. The second equation is off by almost 10%. Depending on how accurate the data needs to be, this could be acceptable.

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@&

Good. However you should be including the units of all quantities at every step of your analysis.

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