Question 32
In this question use g=9.8g = 9.8g=9.8 m s−2^{-2}−2.
Two particles PPP, of mass 4 kg, and QQQ, of mass 5 kg, are connected by a light inextensible string passing over a smooth pulley fixed at the top of a rough plane inclined at an angle θ \theta\,θ to the horizontal, where cosθ=0.8\cos\theta = 0.8cosθ=0.8.
P P\,P lies at rest on the plane with the string parallel to a line of greatest slope, and Q Q\,Q hangs freely 2 m above the ground with the string taut. The coefficient of friction between P P\,P and the plane is 0.2.
The system is released from rest. Assume that Q Q\,Q reaches the ground before P P\,P reaches the pulley.
Find the speed at which Q Q\,Q hits the ground.
3.4 Forces Questions
87 exam-style questions on OCR (MEI) A Level Maths 3.4 Forces, covering 3.4.1 Language relating to forces, 3.4.2 Acceleration due to gravity, 3.4.3 Identify forces and draw force diagrams, 3.4.4 Resultant of concurrent forces, 3.4.5 Equilibrium of a particle, 3.4.6 Resolve a force into components (A-level only), 3.4.7 Equilibrium condition for resultant zero (A-level only), 3.4.8 Forces in equilibrium sum to zero (A-level only), 3.4.9 Equations for a particle in equilibrium (A-level only), 3.4.10 Frictional force and normal contact force (A-level only), 3.4.11 Model friction with F ≤ μR (A-level only), and 3.4.12 Apply Newton's Laws to friction problems (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.