A uniform plank AB AB\,AB has length 6 m and mass 20 kg. It rests on two supports which are 1 m and 5 m from AAA. A person of mass 40 kg walks from the centre of the plank towards BBB.
Find the distance from A A\,A at which the person is standing when the plank is on the point of tilting.
42 exam-style questions on WJEC A Level Maths 4.10 Moments (A-level only), covering 4.10.1 Moments (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.