Problem Does the temperature of a tennis ball affect the height of a bounce?
Hypothesis If we measure the bounce of tennis balls at various temperatures, then the heated ball will bounce the highest.
Variables Independent Variable: temperature of tennis ball Dependent Variable: height of bounce in cm Controlled Variables: meter stick, tennis ball brand, the surface, and the height that the ball is dropped from
Materials 3 new tennis balls Meter stick Hot Plate Freezer Beaker Timer
Procedure 1. Obtain 3 tennis balls: one at room temperature, one that has been heated in a beaker on a hot place for 5 minutes, and one that has been in a freezer for 24 hours 2. Place meter stick vertically on the tile floor with 0 cm pointing down. 3. Place the heated tennis ball at 1 meter. 4. Drop the tennis ball and record the height. 5. Do this 3 times for each tennis ball. 6. Repeat steps 2-5 for the frozen and room temperature tennis ball.
Observations/Analysis Room Temperature Hot plateFreezer Trial 156 cm 70 cm22 cm Trial 261 cm70 cm27 cm Trial 363 cm72 cm 31 cm Height of a Tennis Ball Bounce at Different Temperatures
Observations/Analysis Condition of Tennis Ball Height of Bounce in cm Height of a Tennis Ball Bounce at Different Temperatures
Conclusion Our tennis ball experiment proved our hypothesis correct. The heated tennis ball will bounce higher because the molecules in the rubber of the tennis ball expanded causing a higher bounce. As are trials continued, the tennis balls seemed to adapt to the surrounding temperature. The time the tennis balls were being heated or cooled could have affected are experiment greatly because the more the heat, the higher the bounce. However, the cooler the ball, the lower the bounce. Therefore, the frozen tennis ball bounced the lowest of the three. Each tennis ball bounced right against the meter stick which helped us measure the height of the bounce. We also had a tape measure that reached higher than one meter. The purpose of the tape measure was to measure any bounces that went over one meter. Everything went well and we felt we gathered accurate results.
Reflection If we could change something to make this experiment better we would heat the ball up to higher temperature for a longer amount of time to see if the bounce was even greater than found during our testing. We would also keep the ball in the freezer for a longer period of time to see if the results would vary.