At 70 mph (about 31 metres per second), how does a two-second gap compare with the typical overall stopping distance of 96 metres?
Answer and explanation
Correct answer: D. The gap is about 63 m, roughly 33 m short of the stopping distance
- Step 1: In two seconds the car covers 2 x 31 = 62 or 63 m. Step 2. 96 - 63 = 33 m, so the two-second gap is much shorter than the full stopping distance at that speed. Answer: The gap is about 63 m, roughly 33 m short of the stopping distance. Why not the others: 63 m is not greater than 96 m, 31 m is only one second's travel, and the gap is not equal to the stopping distance.
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