A uniform rod, ABABAB, of length 4 m and mass M M\,M kg, is at rest with A A\,A against a rough vertical wall. The rod supports a sign of mass 4M 4M\,4M at P P\,P where AP=3AP = 3AP=3 m. The rod is held in a horizontal position by a wire attached to B B\,B and to the wall at CCC. The angle between the wire and the rod is α\alphaα, where tanα=815\displaystyle \tan \alpha = \frac{8}{15}tanα=158. The rod is modelled as a uniform rod, the sign is modelled as a particle and the wire is modelled as a light inextensible string.
Find, in terms of MMM, the tension in the wire BCBCBC.
Find the direction of the force exerted on the rod at AAA.
129 exam-style questions on Edexcel A Level Maths Applications of Forces, covering 7.1 Static Particles, 7.2 Modelling with Statics, 7.3 Friction and Static Particles, 7.4 Static Rigid Bodies, 7.5 Dynamics and Inclined Planes, and 7.6 Connected Particles 2. Each one has a worked solution and a mark scheme showing where the marks go.