3.
\begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{ace84823-db30-463e-b24b-f0cd7df73746-06_615_1134_290_409}
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\caption{Figure 3}
\end{figure}
A particle \(P\) of mass 2 kg is attached to one end of a light elastic spring, of natural length 0.8 m and modulus of elasticity 12 N . The other end of the spring is attached to a fixed point \(A\) on a rough plane. The plane is inclined at \(30 ^ { \circ }\) to the horizontal. Initially \(P\) is held at rest on the plane at the point \(B\), where \(B\) is below \(A\), with \(A B = 0.3 \mathrm {~m}\) and \(A B\) lies along a line of greatest slope of the plane. The point \(C\) lies on the plane with \(A C = 1 \mathrm {~m}\), as shown in Figure 3.
The coefficient of friction between \(P\) and the plane is 0.3
After being released \(P\) passes through the point \(C\).
Find the speed of \(P\) at the instant it passes through \(C\).