The Two Second Gap
Often people find it easier to judge distances. The speed limit on the motorway is 70 miles per hour. At this speed, what distance would correspond to a two second gap?
\[70 mph = \frac{70 \times 1609}{3600} = 31.3m/s\]
In two seconds a vehicle traveling at 70 mph travels
\[31.3 \times 2 = 61.6 m\]
and many people find a distance like this easier to measure if there are no 'road furniture', like signs.