In this question use g=9.8g = 9.8g=9.8 m s−2^{-2}−2
A particle A A\,A of mass 2 kg lies on a smooth horizontal table.
A A\,A is attached to one end of a light inextensible string. The string passes over a smooth pulley fixed at the edge of the table, and a particle B B\,B of mass M M\,M kg hangs freely at the other end of the string.
The string between A A\,A and the pulley is horizontal, and the string between the pulley and B B\,B is vertical.
The string will break if the tension in it exceeds 15 N.
The system is released from rest with the string taut.
Show that the acceleration of the system is MgM+2\dfrac{Mg}{M + 2}M+2Mg m s−2^{-2}−2.
Hence show that the tension in the string is 2MgM+2\dfrac{2Mg}{M + 2}M+22Mg N.
Find the set of possible values of M M\,M for which the string does not break.
139 exam-style questions on AQA A Level Maths 3.3 R: Forces and Newton's laws, covering 3.3.1 Concept of a force and Newton's first law, 3.3.2 Newton's second law, 3.3.3 Weight and motion under gravity, 3.3.4 Newton's third law and equilibrium, 3.3.5 Addition of forces and resultants (A-level only), and 3.3.6 Friction (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.