A coach is tested at 30 m/s. It travels 72 m from the moment its brakes are applied until it stops. On a later journey, the same coach is travelling at 20 m/s when the driver detects an obstruction. The driver's reaction time is 0.75 s, and the road conditions and braking force are the same as in the test. What is the minimum distance in which the coach can stop?
32 m32\ \mathrm{m}32 m
47 m47\ \mathrm{m}47 m
63 m63\ \mathrm{m}63 m
87 m87\ \mathrm{m}87 m
126 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.