Stopping Distance

Stopping Distance is a free interactive simulation of the factors that affect how far a car travels before stopping, for GCSE Physics (Edexcel IGCSE 4PH1). Students vary speed, reaction time and road conditions to investigate how each factor changes stopping distance. No login required — includes a worksheet and self-marking quiz.

Aim: To investigate the factors that affect stopping distance.

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Stopping Distance

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Thinking point
Stopping point
Hazard
Thinking Distance
Braking Distance
Hazard
0255075100

Stopping Distance Controls

Explore how different factors affect a vehicle's stopping distance. Adjust the sliders below to see the impact on both thinking distance and braking distance.

51830
14 m/s
0.21.12.0
0.7 seconds

Results

Thinking Distance:0 metres
Braking Distance:0 metres
Total Stopping Distance:0 metres

Stopping Distance Facts

  • Stopping distance = Thinking distance + Braking distance
  • Thinking distance is how far you travel before you start braking (speed × reaction time)
  • Braking distance increases with the square of speed (doubling speed quadruples braking distance)