A driver increases speed from 80 km/h to 120 km/h. By what factor does the braking distance change?
Answer and explanation
Correct answer: B. 2.25
- Step 1: Braking distance is proportional to the square of the speed. Step 2. Factor = (120 ÷ 80)² = 2.25. Answer: 2.25. Why not the others: 1.5 results from having forgotten to square the speed ratio. 3.375 results from having cubed the speed ratio. 3.25 results from having added one to the correct factor.
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?