Suggest why the student waits a short time before recording the temperature at time $t = 0$.
Read the thermometer and record the temperature $\theta$ on the answer line and in Table 3.1. $\theta$ = [BLANK] $^\circ\text{C}$
Using the data in Table 3.1, describe how the water’s rate of cooling changes over the $5.0\,\text{minutes}$.
Calculate the average rate of cooling over the $5.0\,\text{minutes}$ using the equation: average rate of cooling = $\frac{\text{temperature change in }5.0\,\text{minutes}}{5.0}$ average rate of cooling = [BLANK] unit [BLANK]
Using the results in Table 3.1 on page 9 and Table 3.2, suggest how the cotton wool layer has affected the rate at which the water cools.
The student repeats the experiment with the same starting temperature. Suggest how she changes the apparatus so that the temperature after $5.0\,\text{minutes}$ is higher than $71\,^\circ\text{C}$.