Test for motorway drivingYou'll get a load of bolshie negative ninnies who will disagree on principle with youswear at you I would say its a good idea however my concern would be that as its nigh on...
"scott" wrote in message
You are making the mistake of buttuming that the cars have no length. Cars of no length, 2 seconds apart, they would pbutt any given point at the rate of 30 per minute and therefore 1800 per hour.
At 22 mph (32.25 ft-sec) and buttuming a typical car is 14 feet long, each car takes up 78.5 ft of road whilst retaining a 2 second gap. It will take about 2.44 secs for each car to pbutt a given point giving a flow of 1475 cars per hour.
At 70 mph ( 102.66 ft-sec) and buttuming each car is 14 feet long, each car takes up 219.32 ft of road whilst retaining a 2 second gap. It will take 2.13 seconds for each car to pbutt a given point giving a flow of 168 plus 10 cars per hour.
So in theory the higher speed should result in more cars per hour throughput, but drivers don't keep to regular spacing and vehicles aren't of standard length. Ripple effects run through congested traffic which can even mean that traffic stops for no apparent reason. Slower speeds have been shown to reduce the ripple effect and lead to smoother flow which increases throughput.
Ian
