In this question use g=9.8g = 9.8g=9.8 m s−2^{-2}−2.
A rough plane is inclined to the horizontal at an angle α\alphaα, where tanα=512\displaystyle \tan\alpha = \frac{5}{12}tanα=125. A block of mass m m\,m kg is placed on the plane and released from rest. The coefficient of friction between the block and the plane is 25\displaystyle \frac{2}{5}52.
Find the acceleration of the block.
A different block, of mass 2m kg, is placed on the same plane and released from rest. State how the acceleration of this block compares with your answer to part (a), and explain why.
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.