Edexcel M3 2015 June — Question 6

Exam BoardEdexcel
ModuleM3 (Mechanics 3)
Year2015
SessionJune
TopicSimple Harmonic Motion

6. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{00388805-5d60-4327-a10e-c0df74a0cb75-11_186_1042_223_452} \captionsetup{labelformat=empty} \caption{Figure 3}
\end{figure} Two points \(A\) and \(B\) are 6 m apart on a smooth horizontal floor. A particle \(P\) of mass 0.5 kg is attached to one end of a light elastic spring, of natural length 2.5 m and modulus of elasticity 20 N . The other end of the spring is attached to \(A\). A second light elastic spring, of natural length 1.5 m and modulus of elasticity 18 N , has one end attached to \(P\) and the other end attached to \(B\), as shown in Figure 3. Initially \(P\) rests in equilibrium at the point \(O\), where \(A O B\) is a straight line.
  1. Find the length of \(A O\). The particle \(P\) now receives an impulse of magnitude 6 N s acting in the direction \(O B\) and \(P\) starts to move towards \(B\).
  2. Show that \(P\) moves with simple harmonic motion about \(O\).
  3. Find the amplitude of the motion.
  4. Find the time taken by \(P\) to travel 1.2 m from \(O\).