OCR M2 2005 June — Question 3

Exam BoardOCR
ModuleM2 (Mechanics 2)
Year2005
SessionJune
TopicCircular Motion 1

3
\includegraphics[max width=\textwidth, alt={}, center]{35477eb8-59e0-4de6-889c-1f5841f65eec-2_451_533_1676_808} One end of a light inextensible string of length 1.6 m is attached to a point \(P\). The other end is attached to the point \(Q\), vertically below \(P\), where \(P Q = 0.8 \mathrm {~m}\). A small smooth bead \(B\), of mass 0.01 kg , is threaded on the string and moves in a horizontal circle, with centre \(Q\) and radius \(0.6 \mathrm {~m} . Q B\) rotates with constant angular speed \(\omega\) rad s \(^ { - 1 }\) (see diagram).
  1. Show that the tension in the string is 0.1225 N .
  2. Find \(\omega\).
  3. Calculate the kinetic energy of the bead.