cq_1_71

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?

9.8m/s^2

a = `dv/`dt = (vf - v0)/`dt = [(2vAve - v0) - v0]/`dt = [(2`ds/`dt - v0) - v0]/`dt = [(2{2m/0.64s} - 0) - 0]/0.64s = 9.8m/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?

No, the acceleration in this case would be 9.1m/s^2.

a = [(2`ds/`dt - v0) - v0]/`dt = [(2{5m/1.05s} - 0) - 0]/1.05s = 9.1m/s^2

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

These observations are only somewhat consistent with the accepted value of the acceleration of gravity. The first acceleration is, but the second one is not.

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20 min.

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Please respond relative to goal of C.

&#Your work looks very good. Let me know if you have any questions. &#