The Squash Ball Experiment

Method

We set up the apparatus as shown in diagram and then heated the ball to a set temperature. We then dropped it from 70 cm high and measured the bounce. We then repeated that temperature another 4 times to gain an average. We had to be careful with the Bunsen burner and so we wore goggles. To keep the experiment fair the only thing, which we changed each time, was the temperature. We used the same ball through out the experiment and checked the ball was at the same temperature each time. We dropped it onto the same table from the same height as well. The range of temperature we used was from 5 degrees Celsius to 70 degrees Celsius. Some of the results needed to be repeated to make sure that they were accurate.

DIAGRAM OF APPARATUS

Results

Temperature (c)

Measurements (Cm)
        Result
     1 Result
    2 Result

     4 Result
     5 Average
5 10 11 13 12 11 11.9
10 15 21 20 19 13 17.6
20 20 23 21 26 24 22.8
30 25 29 26 26 23 25.8
40 21 21 22 26 28 23.6
50 30 30 29 28 25 28.4
60 31 33 32 35 36 33.4
70 37 31 33 35 37 34.6

Conclusion

From my results I can conclude that as the temperature of the ball raises the height of the bounce gets higher. This is in line with the kinetic theory, which defines that as the ball gets hotter the atoms get more energy and vibrate more. When the ball hits the surface then the atoms are pushed together and because they are vibrating more they push each other further away causing the ball to bounce higher. In this experiment the kinetic theory only lasts for a specific set of temperatures. This is because when the ball hits a certain temperature it starts to melt. At 0 degrees Celsius the ball will still bounce as the atoms are still vibrating. The graph proves that the theory works for this experiment, as it is a straight line to start with. However as the ball gets nearer the critical temperature the extra height it bounces becomes less and less. This is shown as the graph levels off. The sketch graph I drew in my prediction matched the real graph showing that the science I used to explain my prediction was correct.

Evaluation

Looking at my results I can say that they were quite reliable and accurate. I had one anomalous result even after an average over five measurements. I can say that looking at my results when I repeated results they were quite close together. I think that I did the experiment quite well although I found it hard to spot where the ball bounced too. This is why I did an average over 5 measurements. To improve the experiment I would need to use specialist equipment like lasers so I could be sure where the ball bounced too. Ways in which I could extend this experiment are to use a different kind of rubber in the ball so that it doesn't melt at such a low temperature this way I could carry on to see whether the kinetic theory is still right at higher temperatures. Also I would like to see what happened when the ball was at 0 degrees Celsius. I would like to do this to see whether the atoms still vibrated causing the ball to bounce. If it did I would like to carry on getting lower and lower to see whether there was a temperature where the atoms no longer vibrated (Absolute Zero)