A uniform stone lintel ABABAB, of length 101010 metres, rests horizontally in equilibrium on two smooth temporary supports at points PPP and QQQ. The distance APAPAP is 222 metres and the distance BQBQBQ is 333 metres.
The reaction force on the lintel at PPP is 8g8g8g newtons.
(i) Show that the mass of the lintel is 202020 kilograms.
(ii) Find the reaction force, in terms of ggg, on the lintel at QQQ.
The support at QQQ is moved so that the distance BQ=2BQ = 2BQ=2 metres. The lintel remains horizontally at rest in equilibrium. A worker claims that the reaction force at QQQ remains unchanged. Explain, with a reason, whether this claim is correct.
130 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.