Research Question:
How does temperature of a squash ball affect the height of the bounce of a squash ball?
Hypothesis:
I hypothesize that as the number of bounces increases, so will the temperature, and as the temperature increases, the height of the bounce of the squash ball will increase. This is due to the direct proportionality of the temperature and pressure of gases, as in the rubber squash ball there is compressed air.
Variables:
Independent:
Bounces of the Ball causing a change in temperature
This will be varied by the use of a squash racket and bouncing the ball, and the temperature will be a factor to record due to the bounces
The numbers of times the ball will be bounced are 50, 100, 150, 200 and 250.
Dependent Variable:
The height of the ball bounced
For this, knowing that the human eye will not be able to identify the height at which the ball has 0 kinetic energy, a digital camera will be used to record the bounce of the ball and then played back in slow motion to identify the height of the bounce of the ball.
Controls:
Height from which Ball is dropped
A meter stick will be adjusted and set up next to the wall, the squash ball will be released from the top of the meter stick and as soon as it is ready to be released, the video is recorded and the ball is let to be dropped and bounced.
Type of Ball
Only one type of squash ball will be used, and all the squash balls will be brand new because every bounce affects the next.
Method:
First, bouncing it several times causing a difference in temperature warms the squash ball.
* But when the preliminary tests were carried out, it was seen that the change in temperature was very minor when the ball was bounced, therefore the independent variable was altered and a new control was added. *
New set of Variables:
Independent:
Temperature of Squash Ball
This will be varied by the use of water baths
The temperatures that will be used for this investigation will be 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, and 60°C.
Dependent Variable remains the same
Control:
The controls listed above are the same, except another factor is controlled:
The time the squash ball is kept in the water bath
It will be kept in the water bath for 2 minutes to acclimatize to the temperature
Apparatus:
7 Squash Balls
Water Bath
Digital Camera
Meter Stick
Stopwatch
Beaker
Tongs
Thermometer
Method:
Therefore the change in method is:
1. Warm a water bath to 30°C
2. Set up a meter stick to the wall
3. Place the squash ball in a beaker and then in the water bath for 2 minutes
4. Once 2 minutes are up, take the squash ball out of the water bath using tongs to avoid getting burned.
5. Drop it from the top of the meter stick and record the dropping and bouncing of the ball using the digital camera
6. Repeat the above steps for the temperatures of 35°C, 40°C, 45°C, 50°C, 55°C, and 60°C.
7. Repeat these steps twice again for accuracy.
8. Watch the recorded videos and find out the heights of the bouncing balls.
9. Record all the data in tables.
Results:
Raw Data:
For 30°C
For 35°C
For 40°C
For 45°C
For 50°C
For 55°C
For 60°C
Processed Data:
Conclusion:
What can be concluded from the data above is that the height at which a squash ball bounces and the temperature of the squash ball is directly proportional. As the temperature increases so does the height at which the ball bounces, this proves that my hypothesis is correct.
The ball never bounced back up to the same height it was dropped, because it was dropped through the air and it lost some of the gravitational potential energy it started with, as it was lost to thermal energy and sound energy.
The reason why the height of the bounce increased with temperature was due to two factors, one being, since the temperature of the ball increased the air inside the ball becomes pressurized which increase the height at which it bounces, the second factor being that the heat causes the rubber to become more stout.
Evaluation:
I think that the results for my experiment were reliable because I carried out the experiment three times trying to reduce the random error, but if I were to carry it out once again I would have increased the number of trials/attempts to reduce still the random error that it ever-present.
The data seems to be pretty reliable although one cannot be sure if the squash ball did stay the temperature of the water bath as wanted to carry out the experiment. But to try an make sure that the ball was the temperature of the water bath we left the ball in the water bath for 2 minutes for it to acclimatize once the desired temperature was reached. The height from which the ball was dropped was controlled as the greater the distance from the ground, the greater the bounce. Another factor controlled was the type of squash ball used because different squash balls have different bouncing effects and are made of different materials.
Overall I felt that my results were good and reliable as I tried my best to keep the investigation fair.
Though I feel that the experiment was fair, if it were to be repeated or done on a large scale, I would need to eliminate any inaccuracies of measurement, as there is always human error despite the use of technology (in this experiment).
To further this experiment in the classroom other factors such as the way the ball is dropped, or the height from which it is dropped or the size and shape of the ball could be investigated.