Physics coursework

In my experiment I will be heating and cooling a double yellow squash ball to see if it changes the bounce of the squash ball in any way.

My prediction is that when the squash ball is heated to higher temperature the bounce will increase, as the air particles in the ball will have more energy.

Equipment used:

* Motion sensor

* Computer

* 6x Water baths

* 2x Double yellow squash balls

* Thermometer

* Glass beaker

* Ice/Snow

* Retort Stand

Variables

There are some variables that I have to keep the same in this experiment, the pressure in squash balls vary depending on the colour and number of the dots it has. I kept my test fair by keeping the squash ball the same all the way through the experiment. It was a brand new double yellow squash ball. I also had to keep the floor on which I dropped it on to the same, luckily for me all the science labs have the same floor so there was no problem with the surface of the floors.

Method

First of all I decided to choose a suitable height to drop the squash ball from, I chose a height of 1.00 meter because the benches in the labs are exactly that height and It would also be a good place to set up the motion sensor.

After that I moved on to heating the balls, we had water baths which were ideal for accurate temperatures, I left each of the balls in the water for I minute so it was a fair test.

I dropped two new squash balls into varying temperatures ranging from 30 degrees to 80 degrees; I left each of them there for the time I chose earlier of 1 minute. To keep them completely submerged by the water I used my tongs to push the ball down into the water.

I then set up a motion sensor and connected it to my computer this was so I could accurately measure the bounce of the squash ball. Once one of the balls was ready for testing I quickly dried it and rushed over to my desk I then started the sensor and dropped the ball, on my computer screen it recorded the journey of the ball and it also showed the bounce. In each case I wrote the results down, I then repeated the experiment three times for each temperature, this would give me a very accurate reading. This reading was taken from an average of the three results.

Conclusion/Data Interpretation

In my experiment I found that the bounce of the squash ball varied significantly as the ball was heated. In the table you can clearly see that there is a positive correlation between the temperatures of the balls. I heated the balls using a water bath ranging from 0 degres centigrade to 80 degrees centigrade.

Temperature (Celsius)

Test 1

Test 2

Test 3

Average

0

2

4

3

3

20

7

9

8

8

30

14

17

20

17

40

20

20

19

20

50

20

22

23

22

60

26

27

24

26

70

29

30

27

29

80

29

41

36

35

In my graph there was a straight line that showed there was a positive correlation and it followed the rule that most straight line graph’s do, it is the rule of y=mx+c this means that as the gradient increases so does the bounce of the ball.

In my experiment I have proved that a squash ball bounces higher when it is hot, the air particles inside the squash ball are hotter so they have more energy. When this energy is transferred from G.P.E (gravitational potential energy) to kinetic energy the bounce becomes and therefore ultimately has more energy when it hits the floor.

Evaluation

There are a few things which I could have done better in my experiment that would have made the results more accurate.

First of all I would have a dropping device because the room for error using the motion sensor was quite large, I would also try and do the test more than 3 times because it would give an extremely accurate result but unfortunately I didn’t have enough time to do this.

Another thing I found was that the motion sensor found it hard to pick up the bounce of a cold squash ball, as you can tell by my table the bounce was very small at 0 degrees, I would definitely set up a camera or another measuring device if I had to do this test again.

If you look at the table and the graph it is very clear that as the temperature of a squash ball increases so does the bounce.