Edexcel M2 2023 June — Question 3

Exam BoardEdexcel
ModuleM2 (Mechanics 2)
Year2023
SessionJune
TopicCentre of Mass 1

3. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{52966963-2e62-4361-bcd5-a76322f8621e-08_1141_810_287_148} \captionsetup{labelformat=empty} \caption{Figure 1}
\end{figure} \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{52966963-2e62-4361-bcd5-a76322f8621e-08_752_803_484_1114} \captionsetup{labelformat=empty} \caption{Figure 1}
\end{figure} The uniform triangular lamina \(A B C\), shown in Figure 1, has height \(9 y\), base \(B C = 6 x\), and \(A B = A C\) The points \(P\) and \(Q\) are such that \(A P : P C = A Q : Q B = 2 : 1\)
The lamina is folded along \(P Q\) to form the folded lamina \(F\)
The distance of the centre of mass of \(F\) from \(P Q\) is \(d\)
  1. Show that \(d = \frac { 16 } { 9 } y\) The folded lamina is suspended from \(P\) and hangs freely in equilibrium with \(P Q\) at an angle \(\alpha\) to the downward vertical.
    Given that \(\tan \alpha = \frac { 64 } { 81 }\)
  2. find \(x\) in terms of \(y\)