3 different brands of tennis balls, each with a different degree of hardness. Check with the store salesperson, if you are not sure which of these balls are harder/softer. You will need 5 tennis balls from each brand
A tennis ball launcher
Measuring tape ?100 meters
A 1 meter long ruler
Large open field
Assistant to help with measurements
Permanent marker pen
For this experiment, the independent variable is the brand of tennis ball. The dependent variable is the distance traveled by the ball. This is determined by using a measuring tape to measure the distance traveled. The constants (control variables) are the settings and position of the tennis ball launcher, the conditions of the field and the temperature/wind conditions.
The balls are first numbered and marked using a permanent marker pen.
The bounciness of the tennis balls is first determined. They are dropped from a height of 1 meter on to a flat surface and the number of times it bounces is counted with the help of the assistant. The results are recorded in the table 1 below.
The experiment is now moved over to the field. Using a tennis ball launcher, the balls are launched from the same launcher and in the same direction and the distance traveled by each ball is measured and recorded. With the help of a measuring, the distance is measured and recorded in table 2 below.