Two particles P P\,P and Q Q\,Q have masses 7m and km km\,km respectively, where k<7k < 7k<7. They are connected by a light inextensible string which passes over a smooth, fixed pulley. The string is taut, and its two hanging sections are vertical. The system is released from rest, and in the subsequent motion P P\,P moves downwards with acceleration of magnitude 23g\displaystyle \frac{2}{3}g32g.
Explain why the acceleration of Q Q\,Q also has magnitude 23g\displaystyle \frac{2}{3}g32g.
Find, in terms of m m\,m and ggg, the tension in the string.
Find the value of kkk.
30 exam-style questions on Edexcel AS Level Maths Forces and Motion, covering 10.1 Force Diagrams, 10.2 Forces as Vectors, 10.3 Forces and Acceleration, 10.4 Motion in 2 Dimensions, 10.5 Connected Particles, and 10.6 Pulleys. Each one has a worked solution and a mark scheme showing where the marks go.