Fig. 1.2 shows a scale printed on the side of the dropping pipette. Describe the method the learner uses to place $1.0\,\text{cm}^3$ of water into the dropping pipette.
The learner uses a stopwatch to find the time $t$ for the wavefront to move from the centre of the dish outwards and then return to the centre. Fig. 1.4 gives three readings for time $t$. Use the stopwatch readings in Fig. 1.4 to work out a precise value for $t$. Show your working and state your answer to a suitable number of significant figures.
The wavefront speed can be found from the equation $\text{speed} = \frac{\text{distance}}{\text{time}}$. Fig. 1.3 is drawn to a scale of $1{:}2$, so it is half the size of the dish used in the experiment. Calculate the speed of the wavefront using your result from part (b)(i) and a measurement taken from Fig. 1.3.
Identify two causes of uncertainty in this experiment.
Suggest one improvement that could be made to this experiment.