During autumn, rail operators often introduce a temporary reduced speed limit on sections of track affected by fallen leaves. When crushed by heavy train wheels, the leaves form a thin, slippery layer of mulch on the steel rails.
Explain, in terms of forces and stopping distances, why trains must operate at a lower speed under these conditions.
39 exam-style questions on Edexcel GCSE Physics 2.5 Stopping and braking distances, covering 2.5.1 Stopping distance and reaction time, 2.5.2 Factors affecting stopping distance, 2.5.3 Dangers of large decelerations, and 2.5.4 Braking distance and initial speed. Each one has a worked solution and a mark scheme showing where the marks go.