The purpose of this lab is to prove that the acceleration of gravity is 9.8m/s/s. We did this by taking a time lapse photo of a ball dropped with a meter stick next to it. While the ball was dropped, a strobe light was flashing 3000 times per second, which created measurable points of the balls descent. Then we did a few different graphs of the data points by hand and computer.
1. Set up a meter stick vertically against a black background
2. Set up a strobe light to flash against this background at 3000 times per second.
3. Focus a camera to take in the entire length of the meter stick to ensure that the balls entire flight is captured.
4. Pull back the slide to prepare the film.
5. Press and hold the shutter open and drop the ball at the same time.
6. Release the shutter when the ball hits the ground.
7. Wait 30 sec for the picture to develop and record the measurements for each time the ball is shown.
8. Set up a graph with time as the x-axis and your distance measurements on the y-axis.
9. Plot your distance points every .02s, then sketch a best fit curve.
10. Determine the slope at every other data point by drawing tangent lines.
11. The slope found on the tangent lines is the velocity at each instance.
12. Plot a new graph using the velocity data as the new y-axis.
13. Determine the slope of that graph to determine the experimental acceleration
14. Repeat process on computer.
Distance vs. Time
Slopes of Distance vs. Time