A package of weight 25 N lies on a rough ramp inclined at an angle of 35∘ 35^\circ\,35∘ to the horizontal. A horizontal force of 30 N acts on the package and the package is in equilibrium on the point of slipping up the ramp.
Find the coefficient of friction between the package and the ramp.
The 30 N force is removed. Determine whether or not the package moves.
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.