Five drivers each complete five trials using a computer reaction timer in each condition. During the conversation trials, each driver talks with a passenger. The two conditions are tested in a random order. The table shows the mean reaction time for each driver in each condition.
| Driver | Mean reaction time without conversation in s\text{s}s | Mean reaction time while talking with a passenger in s\text{s}s |
|---|---|---|
| P | 0.24 | 0.30 |
| Q | 0.28 | 0.33 |
| R | 0.25 | 0.29 |
| S | 0.32 | 0.31 |
| T | 0.26 | 0.34 |
| Mean for all drivers | 0.27 | 0.31 |
Evaluate the conclusion that talking with a passenger increases the reaction time of every driver.
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.