A Level Mechanics Year 1, Chapter 8 · exam-style questions with mark schemes · constructing a model, modelling assumptions (particle, light, inextensible, smooth, rough, rigid, uniform, bead, wire, peg) and their effects, SI units and converting between units, scalars and vectors, velocity and displacement as vectors, speed, direction and bearings, position after time with constant velocity, two particles moving with constant velocities, choosing and criticising models, comparing and fitting models to data, ropes with mass, mass, weight and the value of g, resultants of forces in magnitude–direction form, a boat in a current and an aircraft in a wind