Find the length of $D$ on Fig. 1.1 to the nearest millimetre, and write it down.
Fig. 1.1 is drawn at one-tenth full size. Write down the real height $H$ of the point of support above the bench.
Fill in the table shown in Fig. 1.2.
Explain why measuring the time for 20 oscillations instead of for 1 oscillation leads to a more accurate value of $T$.
On Fig. 1.3, plot a graph of $T^2 / \text{s}^2$ against $h / \text{cm}$, putting $T^2 / \text{s}^2$ on the $y$-axis and $h / \text{cm}$ on the $x$-axis. Begin both axes at $(0,0)$. Draw the straight line of best fit.
Extend your line so that it meets the $y$-axis. State the intercept $c$ on the $y$-axis.
Calculate the gradient $m$ of your line. Show your working and mark on the graph the values you use in the calculation of the gradient.
Theory states that $H$ is given by $H = \frac{c}{m}$. Use this relation to calculate $H$.
Compare the measured value of $H$ from (a)(ii) with your result in (d). State whether the two values agree and justify your decision.