A student measures his reaction time using a ruler-drop test. He repeats the test ten times.
Why does he repeat the test?
To make the ruler fall with a greater acceleration
To spot any anomalous results and calculate a mean
To make his reaction time shorter on every attempt
To avoid having to measure the distance the ruler falls
50 exam-style questions on OCR GCSE Physics 8.1 Physics on the move, covering 8.1.1 Typical everyday speeds, 8.1.2 Typical everyday accelerations, 8.1.3 Ratios, units and rates on the road, 8.1.4 Human reaction times, 8.1.5 Factors affecting stopping distance, 8.1.6 Stopping distances at different speeds, 8.1.7 Dangers of large decelerations, 8.1.8 Estimating forces in road situations, and 8.1.9 Estimating the effects of large accelerations. Each one has a worked solution and a mark scheme showing where the marks go.