Bubble wrap can be used as an insulator around a container.
Chloe conducts an experiment to investigate how the number of layers of bubble wrap wrapped around a copper can affects the time it takes for hot water in the can to cool down.
Chloe starts the experiment with a copper can, a roll of bubble wrap, scissors, and a kettle of hot water.
Describe how Chloe conducts this experiment.
You should write about:
- the extra equipment Chloe needs and what this equipment measures
- Chloe's method
- a variable that needs to be controlled.
Sam does the same experiment using the exact same method as Chloe.
The table below shows the students' results when there is no bubble wrap insulation around the copper can:
| Time (min) | Temperature of Chloe (∘C^\circ\text{C}∘C) | Temperature of Sam (∘C^\circ\text{C}∘C) |
|---|---|---|
| 0 | 85 | 85 |
| 2 | 77 | 76 |
| 4 | 71 | 71 |
| 6 | 66 | 67 |
| 8 | 63 | 62 |
| 10 | 60 | 60 |
Describe the trend shown by the students' results.
Describe how the table shows that the students' results are reproducible.
The students plot a graph of temperature against time, shown below:
State two reasons why the graph does not show that the temperature of the water is directly proportional to time.