"David Cantrell" wrote in message
...
On Fri, Jun 01, 2007 at 12:00:35AM +0100, Rob (UK) wrote:

To quote Jeremy Clarkson he said that "If you reduce the number of
lanes from 2 to 1 then you have to double the speed to get the same
number of cars through per hour"

Thus demonstrating that he failed O level physics.

Kinetic energy is proportional to the *square* of a car's speed.
Consequently the safe distance between cars also goes up approximately
with the square of their speed. So in fact increasing speed will reduce
throughput.

ISTR the maximum throughput is achieved at something between 15 and 20
miles/hour.

D A Stocks