4.
\begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{717c6949-db0f-4c2b-87a6-a7adf8c30a9e-06_415_981_237_475}
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\caption{Figure 1}
\end{figure}
The trapezium \(A B C D\) is a uniform lamina with \(A B = 4 \mathrm {~m}\) and \(B C = C D = D A = 2 \mathrm {~m}\), as shown in Figure 1.
- Show that the centre of mass of the lamina is \(\frac { 4 \sqrt { } 3 } { 9 } \mathrm {~m}\) from \(A B\).
The lamina is freely suspended from \(D\) and hangs in equilibrium.
- Find the angle between \(D C\) and the vertical through \(D\).