Two particles A A\,A and B B\,B have mass of 2 kg and m kgm\text{ kg}m kg respectively, where m<2m < 2m<2. The particles are connected by a light inextensible string which passes over a smooth, fixed pulley. Initially A A\,A is 3 m above horizontal ground. The string is released from rest with the string taut and the hanging parts of the string vertical. After A A\,A has been descending for 2.5 s it strikes the ground. Particle A A\,A reaches the ground before B B\,B reaches the pulley.
Show that the acceleration of A A\,A as it descends is 0.96 ms-2
Show that the mass of B B\,B is 1.64 kg
State how you have used the information that the string is inextensible.
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.