Ball Drop

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course phy 201

12/12 1:30

Ball Drop

You dropped a ball from a measured and/or estimated height and estimated the time required for it to drop.

Insert a copy of your data here, along with any previously submitted work you wish to include:

****

`ds=1m or 100cm

`dt=.5s

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What do you think was the percent uncertainty in the measurement of height?

****

.1% uncertainty

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What do you think was the percent uncertainty in the measurement of the time of fall?

****

25% uncertainty +-.25s

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What were the average velocity and, assuming acceleration to have been uniform, the acceleration of the falling ball?

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Vave=`ds/`dt

1m/.5s= 2 m/s

a=`dv/`dt

4(m/s)/.5s= 8(m/s^2)

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Based on your uncertainty estimates for time of fall and height, what is the percent uncertainty in the acceleration as you observed it?

****

i think about 25%

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"

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At 25% uncertainty in the time of fall is reasonable, given the difficulty in estimating such a short time.

Division by the time interval would therefore result in about a 25% uncertainty in the result.

Since we divide by the time interval twice, obtaining a 25% uncertainty each time, we get about a 50% uncertainty in our final result.

Your 8 m/s^2 estimate is easily within +-50% of the accepted 9.8 m/s^2 acceleration of gravity, so your results are consistent with accepted values, within the uncertainty of your observations.

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