Is it possible to increase the traffic flow by increasing the maximum allowed speed on the road?
The answer is NO. Due to reaction time, we need to keep the car in front of us a minimum distance.
If the reaction time is dt, and the speed of the car is v. You need to keep at least s=v*dt to be safe.
If the car is moving faster, the safety distance need to be increase proportionally.

There are 3 lanes in the following applet. The maximum speed [b]Vmax[/b] for each lanes are different.
You can change Vmax, if you click Vmax label in the applet and enter your value into the textfield at the top.
Remember to hit ENTER when you are done (and the applet will accept your new value).
Nmax is the allowed maximum of cars on the road.
N is the current number of cars on the road, and n is the total number of cars pass the right edge.
I hope you can enjoy the related physics!

Related topic: [url=]Reaction time measurement[/url] , [url=]Reaction time and car accident[/url], [url=]Traffic Light System[/url]