| Exam Board | OCR |
|---|---|
| Module | M2 (Mechanics 2) |
| Marks | 8 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Circular Motion 1 |
| Type | Smooth ring on rotating string |
| Difficulty | Standard +0.3 This is a standard conical pendulum problem requiring resolution of forces and circular motion equations. The geometry is given, making it straightforward to find angles and apply T cos θ = mg and T sin θ = mω²r. While it involves multiple steps across three parts, each follows routine M2 procedures without requiring novel insight or complex problem-solving. |
| Spec | 6.02e Calculate KE and PE: using formulae6.05a Angular velocity: definitions6.05b Circular motion: v=r*omega and a=v^2/r6.05c Horizontal circles: conical pendulum, banked tracks |
\includegraphics{figure_3}
One end of a light inextensible string of length 1.6 m is attached to a point $P$. The other end is attached to the point $Q$, vertically below $P$, where $PQ = 0.8$ m. A small smooth bead $B$, of mass 0.01 kg, is threaded on the string and moves in a horizontal circle, with centre $Q$ and radius 0.6 m. $QB$ rotates with constant angular speed $\omega$ rad s$^{-1}$ (see diagram).
\begin{enumerate}[label=(\roman*)]
\item Show that the tension in the string is 0.1225 N. [3]
\item Find $\omega$. [3]
\item Calculate the kinetic energy of the bead. [2]
\end{enumerate}
\hfill \mbox{\textit{OCR M2 Q3 [8]}}