Question 27
A brick of weight 15 N lies on a rough plane inclined at an angle of 25° 25°\,25° to the horizontal. A horizontal force of magnitude 14 N acts on the brick, in the vertical plane containing a line of greatest slope. The brick is in equilibrium, on the point of slipping up the plane.
a.[5]
Find the coefficient of friction between the brick and the plane.
b.[2]
The 14 N force is now removed. Determine whether the brick remains in equilibrium.
3.3 R: Forces and Newton's laws Questions
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.