A uniform timber plank, of mass mmm kilograms and length 4.0 m, rests on a flat rooftop. The end of the plank, BBB, projects 1.5 m beyond the edge of the roof, AAA.
A toolbox of mass 20 kg is placed on the plank at the midpoint of the overhanging section ABABAB. The plank is in equilibrium and on the point of tilting about AAA. Show that m=30m = 30m=30.
The toolbox is removed. A number, nnn, of identical stone tiles, each of mass 4 kg, are stacked on the plank at a point 0.2 m from the end BBB. Determine the maximum value of nnn such that the plank does not tilt.
State one assumption you have made about the plank.
Practise Edexcel A Level Maths Applications of Forces with exam-style questions for A Level Maths. 47 questions covering Static Particles, Modelling with Statics, Friction and Static Particles, Static Rigid Bodies, Dynamics and Inclined Planes, and Connected Particles 2, matched to the Edexcel A Level Maths (9MA0) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.