(i)You are provided with two metre rules and other necessary apparatus.
(ii)Place one of the rules on a knife edge and determine its centre of gravity C. Mark this position with a piece of chalk.
(ii)Read and record the mass MR of the metre rule written on the reverse side of it.
(iv)Attach the mass M = 100 g firmly to the rule AB at C using sellotape.
(v)Suspend the metre rule by two parallel thread of length h = 40 cm each at the 10 cm and 90 cm marks. Ensure that the graduated face of the metre rule is facing upwards.
(vi)Set the rule AB into a small angular oscillation about the vertical axis through its centre of gravity.
(vii)Determine the time t for 20 complete oscillations. Evaluate the period T and T2.
(viii)Read and record the value of d in metres.
(ix)Keeping d constant throughout the experiment, repeat the procedure for other values of h = 50, 60, 70 and 80 cm. In each case determine the corresponding values of t, T and T2. Tabulate your readings.
(x)Plot a graph of T2on the vertical axis and h on the horizontal axis.
(xi)Determine the slope s, of the graph.
Evaluate k = s
where Q = 2
(xii)State two precautions taken to ensure accurate results
(b) (i) Define the term couple as it relates to rotational or oscillatory systems.
(ii) Give two practical applications of a couple in everyday life.