What effect does vehicle speed have on driver reaction time?
Show the correct answer
Correct answer
C. The higher the speed, the less time to react.
Explanation
The question is about the effect of vehicle speed on the driver's reaction. The higher the speed, the less time to react - answer C.
The Road Traffic Act requires you to drive at a speed that ensures control of the vehicle, taking into account the traffic conditions, and physics explains why. A driver's reaction time - from noticing a danger to pressing the brake - is about a second and does not depend on speed; what depends on speed is how far you travel in that time: at 50 km/h about 14 m, at 100 km/h about 28 m, at 140 km/h almost 40 m. The faster you drive, the faster you approach an obstacle and the fewer seconds you have from the moment you see it to the moment you hit it. Answer A is wrong, because this relationship is very strong; answer B is wrong, because at a higher speed a person does not react faster - on the contrary, the field of view narrows and it is harder to judge distance. That is why at a higher speed you need a larger following distance from the vehicle in front and a longer section of visible road.
Legal basis: Art. 19 para. 1 and para. 2 point 3 of the Road Traffic Act (Prawo o ruchu drogowym)