Edexcel M2 2023 October — Question 6 9 marks

Exam BoardEdexcel
ModuleM2 (Mechanics 2)
Year2023
SessionOctober
Marks9
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicMoments
TypeRod hinged to wall with string support
DifficultyStandard +0.3 This is a standard M2 moments problem requiring equilibrium conditions (sum of moments = 0, resolving forces) with straightforward geometry. The triangle ACD is equilateral (all sides 5a), giving the angle directly. Students take moments about A, resolve horizontally and vertically, then find the resultant force. While multi-step, it follows a well-practiced routine with no novel insight required, making it slightly easier than average.
Spec3.03m Equilibrium: sum of resolved forces = 03.04b Equilibrium: zero resultant moment and force

6. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{f180f5f0-43c5-4365-b0d8-7284220b481e-20_593_745_246_667} \captionsetup{labelformat=empty} \caption{Figure 4}
\end{figure} A uniform \(\operatorname { rod } A B\) has length \(8 a\) and weight \(W\).
The end \(A\) of the rod is freely hinged to a fixed point on a vertical wall.
A particle of weight \(\frac { 1 } { 4 } W\) is attached to the rod at \(B\).
A light inelastic string of length \(5 a\) has one end attached to the rod at the point \(C\), where \(A C = 5 a\). The other end of the string is attached to the wall at the point \(D\), where \(D\) is above \(A\) and \(A D = 5 a\), as shown in Figure 4. The rod rests in equilibrium.
The tension in the string is \(T\).
  1. Show that \(T = \frac { 6 } { 5 } \mathrm {~W}\)
  2. Find, in terms of \(W\), the magnitude of the force exerted on the rod by the hinge at \(A\).

6.

\begin{figure}[h]
\begin{center}
  \includegraphics[alt={},max width=\textwidth]{f180f5f0-43c5-4365-b0d8-7284220b481e-20_593_745_246_667}
\captionsetup{labelformat=empty}
\caption{Figure 4}
\end{center}
\end{figure}

A uniform $\operatorname { rod } A B$ has length $8 a$ and weight $W$.\\
The end $A$ of the rod is freely hinged to a fixed point on a vertical wall.\\
A particle of weight $\frac { 1 } { 4 } W$ is attached to the rod at $B$.\\
A light inelastic string of length $5 a$ has one end attached to the rod at the point $C$, where $A C = 5 a$.

The other end of the string is attached to the wall at the point $D$, where $D$ is above $A$ and $A D = 5 a$, as shown in Figure 4.

The rod rests in equilibrium.\\
The tension in the string is $T$.
\begin{enumerate}[label=(\alph*)]
\item Show that $T = \frac { 6 } { 5 } \mathrm {~W}$
\item Find, in terms of $W$, the magnitude of the force exerted on the rod by the hinge at $A$.
\end{enumerate}

\hfill \mbox{\textit{Edexcel M2 2023 Q6 [9]}}