A light elastic string, of natural length \(4a\) and modulus of elasticity \(8mg\), has one end attached to a fixed point \(A\). A particle \(P\) of mass \(m\) is attached to the other end of the string and hangs in equilibrium at the point \(O\).
- Find the distance \(AO\).
[2]
The particle is now pulled down to a point \(C\) vertically below \(O\), where \(OC = d\). It is released from rest. In the subsequent motion the string does not become slack.
- Show that \(P\) moves with simple harmonic motion of period \(\pi\sqrt{\frac{2a}{g}}\).
[7]
The greatest speed of \(P\) during this motion is \(\frac{1}{2}\sqrt{(ga)}\).
- Find \(d\) in terms of \(a\).
[3]
Instead of being pulled down a distance \(d\), the particle is pulled down a distance \(a\). Without further calculation,
- describe briefly the subsequent motion of \(P\).
[2]