# Free Fall

## Discussion:

VideoPointTM software gives you the ability to analyze motions captured in digital movies. In this lab, you will analyze the motion of a ball in free fall.

## Analysis & Questions:

1. Write a brief description of the position vs. time graph for the ball's motion.
2. On your position vs. time graph, identify the portion of the graph that represents the time period when the ball was moving upward, and the portion of the graph that represents the time period when the ball was moving downward. Also, identify the instant (as nearly as you can) when the ball was at its highest point.
3. Write a brief description of the velocity vs. time graph for the ball's motion.
4. On your velocity vs. time graph, identify the portion of the graph that represents the time period when the ball was moving upward, and the portion of the graph that represents the time period when the ball was moving downward. Also, identify the instant (as nearly as you can) when the ball was at its highest point. (These time periods probably should match the times in question 1, shouldn't they?)
5. Write a short description of what the velocity was doing as the ball was going upward, and when the ball was going downward. What was the ball's velocity when it was at its highest point?
6. According to the best-fit equation, what is the slope of the velocity vs. time graph for the ball's motion? Why does it have that slope?
7. Did the ball have a different acceleration as it was going upward than when it was going downward? How do you know?
8. What was the ball's acceleration when it was at its highest point? How do you know this?
9. Write a brief description of the acceleration vs. time graph for the ball's motion. What does the graph tell you about the acceleration of the ball while it was in the air?
10. Looking at the best-fit equation for your acceleration vs. time data, what is the physical significance of the y-intercept of the line? What is the physical significance of the slope of this line?

last update October 10, 2001 by JL Stanbrough