A minibus is driven on a dry test track at two different speeds. On each run, the driver's reaction time and the total stopping distance are measured.
| Speed in km/h\mathrm{km/h}km/h | Reaction time in s\mathrm{s}s | Stopping distance in m\mathrm{m}m |
|---|---|---|
| 45 | 0.64 | 18 |
| 90 | 0.80 | 60 |
1 m/s=3.6 km/h1\ \mathrm{m/s}=3.6\ \mathrm{km/h}1 m/s=3.6 km/h
Calculate the ratio of the braking distance at 90 km/h to the braking distance at 45 km/h.
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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.