A driver travelling at 108 km/h needs 1.5 s to react to a hazard. How far does the car travel before the driver starts to brake?
Answer and explanation
Correct answer: D. 45 m
- Step 1: Speed in m/s = 108 ÷ 3.6 = 30 m/s. Step 2. Distance = 30 × 1.5 = 45 m. Answer: 45 m. Why not the others: 162 m results from having treated km/h as m/s. 22.5 m results from having halved the reaction time. 90 m results from having doubled the reaction time.
Practise more Geschwindigkeit, Abstand und Überholen.
Free questions with an explanation for every one, and full timed Driving Theory Test (Car) - Switzerland mock tests.
More Geschwindigkeit, Abstand und Überholen questions
- A driver increases speed from 60 km/h to 120 km/h. By what factor does the braking distance change?
- How many minutes does a car need for 10 km at a constant 50 km/h?
- Using the Swiss rule of thumb (reaction distance in metres = speed in km/h ÷ 10 × 3), how far does a car travelling at 90 km/h move during t…
- Using the Swiss rule of thumb (braking distance in metres = (speed in km/h ÷ 10)², dry road), what is the braking distance at 100 km/h?
- What is the general speed limit on a semi-motorway (Autostrasse)?
- A driver travelling at 126 km/h needs 2 s to react to a hazard. How far does the car travel before the driver starts to brake?