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\begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{4b703cf9-b3d3-4210-b57b-89136595f8a5-04_305_748_260_699}
\captionsetup{labelformat=empty}
\caption{Fig. 1}
\end{figure}
A rectangular block \(B\) of weight 12 N lies in limiting equilibrium on a horizontal surface. A horizontal force of 4 N and a coplanar force of 5 N inclined at \(60 ^ { \circ }\) to the vertical act on \(B\) (see Fig. 1).
- Find the coefficient of friction between \(B\) and the surface.
\begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{4b703cf9-b3d3-4210-b57b-89136595f8a5-04_307_751_1000_696}
\captionsetup{labelformat=empty}
\caption{Fig. 2}
\end{figure}
\(B\) is now cut horizontally into two smaller blocks. The upper block has weight 9 N and the lower block has weight 3 N . The 5 N force now acts on the upper block and the 4 N force now acts on the lower block (see Fig. 2). The coefficient of friction between the two blocks is \(\mu\). - Given that the upper block is in limiting equilibrium, find \(\mu\).
- Given instead that \(\mu = 0.1\), find the accelerations of the two blocks.