Air Resistance of a falling tennis ball
07/04/08 21:25 Filed in: Physics
Suppose I want to have a lab activity with a dropping
tennis ball. Do I need to worry about air resistance
or can I assume there is none? This is a that was
recently asked of me. Below is my answer:
- To model the air resistance of a tennis ball, I will use the following:
Where:
Where ρ is the density of air, C is the drag coefficient and A is the cross sectional area of the ball. Here are the values I used:
The next step is to just use numerical modeling techniques (described here)
The following data is obtained. This graph shows the vertical position of both a tennisball and a ball with no air resistance.
So, what is the answer? The answer depends on your needs. If you are just dropping the ball less than 10 meters, the error will not be too significant. If you are want super accurate results or you are dropping it a long way you should use a different object (unless you want to deal with air resistance).
