Particle P, with mass $0.7\text{ kg}$, is connected to one end of a light inextensible string of length $0.5\text{ m}$. The other end is fixed at point $A$, which lies $h\text{ m}$ above a smooth horizontal surface. $P$ remains in contact with the surface and undergoes uniform circular motion about the point on the surface directly below $A$.
(i)[4]
Taking $h = 0.14$, find an inequality for the angular speed of $P$.
(ii)[7]
If instead the magnitude of the force exerted by the surface on $P$ is $1.4\text{ N}$ and the speed of $P$ is $2.5\text{ m s}^{-1}$, calculate the tension in the string and the value of $h$.
Worked solution & mark scheme
This 11-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Applies $T\cos\theta = 0.7g$” …