Elise Livingston                                                                    

Free Fall Lab

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 Purpose:
     The purpose of the Free Fall Lab was to use our mental and technological skills to determine the acceleration of an object at different points as it is dropped from different heights. The ultimate goal of the lab was to acquaint us with the concept of acceleration and to allow us to better understand it.

Equipment:
- Coffee Filters
- A meter stick or other stationary method of measurement
- Flip Camera
- Computer with LoggerPro software and a moviemaking software
Procedure:
     The procedure of this lab was fairly simple. You have an object (in our case, coffee filters) and some means of measurement. We had a long piece of paper that was marked in meters and another, shorter, board that was marked in centimeters.  
     The coffee filters were dropped from a height of 6.4 m and of 71 cm. Both times, we used the Flip camera to film the drops. Once filmed, we put the videos on the computer and used a movie making software to look at each frame of the drops. At each frame, we recorded the time and the position of the coffee filters as shown on the screen. 
     Once we gathered our data, we put it into LoggerPro and constructed position versus time graphs of each drop. From these graphs, we were able to analyze the acceleration of the object.
Data for 6.4m drop

   Time (s)                 Distance Dropped (m)
         0                                 0

      0.27                             0.3

       0.4                              0.9

       0.54                            1.3

       0.67                            1.9

       0.8                              2.7

      0.94                             3.5

      1.07                             4.4

      1.2                               5.1

      1.27                             5.4
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Data for 71 cm drop

  Time (s)             Distance dropped (cm)
     0                              0

  0.07                          15

  0.13                          22

   0.2                            42

  0.27                          55

 
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Data Analysis:
     Our data shows that as the coffee filters dropped from both heights, their speed increased. This is shown by the parabolic curve of the position versus time graphs. This along with the equations created by the LoggerPro software, allow us to observe the acceleration of the motion. In order to obtain the actual acceleration of the motion, we would take the second derivative of the position versus time curve.
Conclusion:
     This lab fulfilled its purpose as to allow us to better understand the concept of acceleration. We learned the relationship between position versus time and acceleration. However, it is possible that our data is flawed. We constructed the paper with the meter marks on it ourselves, which means that there could be come slight inconsistencies. Also, once the videos were transfered to the computer, the coffee filters were blurred in the different frames. This meant that we had to do our best to guess where exactly the coffee filter was. However, at times, our guessing was probably off by a slight amount. There is also the great probability of human error, as there is in any lab. In order to decrease this margin of error, we would need much more precise measuring devices. It might also be helpful to approach the lab with either a much higher speed camera and software or a motion detector would lend to more accurate results. However, the lab did complete it's job by helping us to understand acceleration.