phy121
Your 'cq_1_7.1' 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 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 m / .64 sec
vAve = 3.125 m/s
vf = 2vAve
vf = 6.25 m/s
a = ‘dv/’dt
a = 6.25 m/s /.64 s
a = 9.77 m/s^2
• 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 m / 1.05 s
vAve = 4.76 m/s
vf = 2(4.76 m/s) = 9.52 m/s
a = 9.52 m/s / 1.05
a = 9.07
Though close, this acceleration is not the same as the first example.
• 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 example is consistent with the accepted value of the acceleration of gravity, and the second example is close, but not the same. The second example may be within the margin of error, however.
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10 minutes
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Excellent.