| Exam Board | CAIE |
|---|---|
| Module | M1 (Mechanics 1) |
| Year | 2011 |
| Session | June |
| Marks | 6 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Forces, equilibrium and resultants |
| Type | Smooth ring on string |
| Difficulty | Moderate -0.5 This is a straightforward equilibrium problem requiring resolution of forces in two perpendicular directions. The setup is clearly defined with a right angle constraint, leading to a standard system of two equations in two unknowns (T and θ), followed by routine trigonometry to find θ. While it requires careful diagram interpretation and systematic force resolution, it involves only standard M1 techniques with no novel insight or complex multi-step reasoning. |
| Spec | 3.03m Equilibrium: sum of resolved forces = 03.03n Equilibrium in 2D: particle under forces |
I notice that the content you've provided only contains "Question 3:" followed by three instances of "3" with no actual marking scheme content to clean up.
Could you please provide the complete mark scheme text that needs to be cleaned? Once you share the full content (including marking annotations like M1, A1, B1, etc.), I'll be happy to convert the unicode symbols to LaTeX notation and format it clearly.
3\\
\includegraphics[max width=\textwidth, alt={}, center]{d5acfe31-8614-4508-ac5b-865e15a1f539-2_661_565_1069_790}
A small smooth ring $R$ of weight 8.5 N is threaded on a light inextensible string. The ends of the string are attached to fixed points $A$ and $B$, with $A$ vertically above $B$. A horizontal force of magnitude 15.5 N acts on $R$ so that the ring is in equilibrium with angle $A R B = 90 ^ { \circ }$. The part $A R$ of the string makes an angle $\theta$ with the horizontal and the part $B R$ makes an angle $\theta$ with the vertical (see diagram). The tension in the string is $T \mathrm {~N}$. Show that $T \sin \theta = 12$ and $T \cos \theta = 3.5$ and hence find $\theta$.
\hfill \mbox{\textit{CAIE M1 2011 Q3 [6]}}