A block of mass 25 kg, is at rest on a rough horizontal floor. The coefficient of friction between the block and the floor is 0.4. A force of F F\,F N is pulling the block at an angle of 20∘ 20^\circ\,20∘ to the horizontal. The block is on the point of sliding.

Find the value of FFF.
108 exam-style questions on Edexcel A Level Maths Forces and Friction, covering 5.1 Resolving Forces, 5.2 Inclined Planes, and 5.3 Friction. Each one has a worked solution and a mark scheme showing where the marks go.