A uniform beam AB AB\,AB of length 10 m and mass 20 kg is used as a ladder. End A A\,A is on rough horizontal ground and the beam rests in limiting equilibrium against a smooth horizontal rail at point CCC, where AC=8AC = 8AC=8 m. The beam is inclined to the horizontal at an angle α\alphaα, where tanα=15/8\tan \alpha = 15/8tanα=15/8. The coefficient of friction between the beam and the ground is μ\muμ.
Find the value of μ\muμ.
3 exam-style questions on OCR A Level Maths 3.3.21 Static and limiting equilibrium on a rough surface (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.