On a wet dual carriageway you use the four-second gap, travelling at 50 mph (about 22 metres per second). About how far behind the vehicle in front should you be?
Answer and explanation
Correct answer: A. About 90 metres
- Step 1: Distance equals speed multiplied by time: 22 x 4. Step 2. 22 x 4 = 88 m, so the gap is about 90 m. Answer: About 90 metres. Why not the others: 45 m is a two-second gap, 22 m is a one-second gap, and 180 m would need about eight seconds.
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