Which factor primarily determines stopping distance for an EVOC vehicle?

• A. Vehicle color
• B. Speed
• C. Engine type
• D. Number of occupants

Answer: (B)

Speed determines stopping distance because it sets how much kinetic energy the vehicle must dissipate and how far you travel while reacting. The stopping distance is made up of two parts: the distance traveled while you perceive and react to a hazard, and the braking distance. The reaction distance grows directly with speed (you cover more ground in the same reaction time), and the braking distance increases even more steeply with speed because the energy to be dissipated rises with the square of velocity. In practical terms, doubling your speed greatly lengthens how far you must travel to stop, under the same road and braking conditions.

The other factors listed don’t change braking performance in the same way. Vehicle color has no effect on braking. Engine type doesn’t altering the basic physics of stopping, and while carrying more occupants adds weight, that impact is small compared with the effect of speed, except in extreme loading. So speed is the primary determinant of stopping distance in EVOC driving.