cq_1_071

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.

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

`ds = v0 * `dt + .5 * a * `dt^2

2 m = 0 m/s * .64 s + .5 * a * (.64 s)^2

2 m = .5 * a * .4096 s^2

4 m = a * .4096 s^2

9.77 m/s^2 = a

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

`ds = v0 * `dt + .5 * a * `dt^2

5 m = 0 m/s * 1.05 s + .5 * a * (1.05 s)^2

5 m = .5 * a * 1.1025 s^2

10 m = a * 1.1025 s^2

9.07 m/s^2 = a

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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 observation follow the value, in that it would round to 9.8 m/s^2. The second observations do not appear to be correct, in that they do not follow the accepted value.

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Copy and paste your work into the box below and submit as indicated:

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10 minutes

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&#Very good responses. Let me know if you have questions. &#