| Exam Board | Edexcel |
|---|---|
| Module | M3 (Mechanics 3) |
| Session | Specimen |
| Marks | 7 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Circular Motion 1 |
| Type | Conical pendulum – horizontal circle in free space (no surface) |
| Difficulty | Standard +0.3 This is a standard conical pendulum problem requiring basic application of circular motion principles and resolving forces. Students must use Pythagoras to find the vertical height (12l), resolve tension vertically (T cos θ = mg) and horizontally (T sin θ = mv²/r), then eliminate T. The geometry is straightforward (3-4-5 triangle scaled), and the method is a textbook exercise with no novel insight required, making it slightly easier than average. |
| Spec | 6.05c Horizontal circles: conical pendulum, banked tracks |
\includegraphics{figure_1}
A garden game is played with a small ball $B$ of mass $m$ attached to one end of a light inextensible string of length $13l$. The other end of the string is fixed to a point $A$ on a vertical pole as shown in Figure 1. The ball is hit and moves with constant speed in a horizontal circle of radius $5l$ and centre $C$, where $C$ is vertically below $A$. Modelling the ball as a particle, find
\begin{enumerate}[label=(\alph*)]
\item the tension in the string, [3]
\item the speed of the ball. [4]
\end{enumerate}
\hfill \mbox{\textit{Edexcel M3 Q1 [7]}}