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\includegraphics[max width=\textwidth, alt={}, center]{a20a6641-d771-4c89-b40f-168a0c61f99d-3_577_693_1740_724} A particle \(P\) of mass 0.2 kg is attached to the mid-point of a light elastic string of natural length 5.5 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 6 m apart. \(P\) is held at rest at a point 1.25 m vertically above the mid-point of \(A B\) and then released. \(P\) travels a distance 5.25 m downwards before coming to instantaneous rest (see diagram). By considering the changes in gravitational potential energy and elastic potential energy as \(P\) travels downwards, find the value of \(\lambda\).