(a)[2]
Define the radian in words.
(b)
A stone with weight $3.0\,\text{N}$ is glued to one end $P$ of a rigid rod $CP$, as illustrated in Fig. 1.1. The rod is turned about end $C$ so that the stone travels in a vertical circle of radius $85\,\text{cm}$. The angular speed $\omega$ of the rod and stone is slowly raised from zero until the glue fails. The glue holding the stone fails when the tension in it is $18\,\text{N}$. For the position of the stone at which the glue fails:
(b(i))[1]
On the dotted circle in Fig. 1.1, mark the stone’s position with the letter $S$.
(b(ii))[4]
Calculate the angular speed $\omega$ of the stone.