She releases the ball from a height of $80\,\text{cm}$ above the bench. After one bounce, the ball rises to a greatest height $h$ of $55\,\text{cm}$. On Fig. 3.1, draw the ball when $h = 55\,\text{cm}$.
On Fig. 3.1, indicate the position of the student’s eye so that the ball at a height of $55\,\text{cm}$ is viewed correctly.
She carries out the procedure three more times and records these values for $h$: $54\,\text{cm}$, $57\,\text{cm}$ and $53\,\text{cm}$. Use all her results to determine the mean value of the maximum height $h$ reached. Give your answer to an appropriate number of significant figures.
The student uses a metre rule with millimetre graduations. Suggest why her results are not written to the nearest millimetre.
The student repeats the procedure but now drops the ball from a height of $10\,\text{cm}$. Suggest why she now finds the maximum height reached difficult to measure.