5
\includegraphics[max width=\textwidth, alt={}, center]{022776e2-80bb-4e73-a309-8cd972ae7377-3_287_1068_1306_536} A light elastic string has natural length 2 m and modulus of elasticity \(\lambda \mathrm { N }\). The ends of the string are attached to fixed points \(A\) and \(B\) which are at the same horizontal level and 2.4 m apart. A particle \(P\) of mass 0.6 kg is attached to the mid-point of the string and hangs in equilibrium at a point 0.5 m below \(A B\) (see diagram).

1. Show that \(\lambda = 26\).
   \(P\) is projected vertically downwards from the equilibrium position, and comes to instantaneous rest at a point 0.9 m below \(A B\).
2. Calculate the speed of projection of \(P\).