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by iso1210 1725 days ago
> When you're on the open road and the speed limit is 55mph, but everyone is going 80mph+, then anyone going the speed limit is a hazard

Surely it's the ones doing 80mph that are the hazzard

2 comments

No, it's the opposite in a situation where people are mostly going 80 and only a few are doing the speed limit. Try traveling down interstate 95, this is an every day situation.

Look at traffic as a fluid: A stream is calm when the water flows at the same speed and direction, when there is nothing to get in the way. Put a rock into the stream and now water has to move around it, causing flow patterns that collide. Traffic can be looked at as a fluid in the same way. If you want it to flow without friction, it all needs to go the same speed in one direction. Accidents and traffic slow-downs are caused when people merge and people have to slow down unexpectedly, which is going to happen when you're going 30mph under the prevailing traffic speed.

Yes, the person going 55 is following the law, but the law was written in a faraway room, a long time ago, by people not driving on the road in that instant. Sometimes in the instant, following the law is not the safe thing to do. It's the same reason it's not safe to go 25 in a 55, and that trucks are required to put their flashers on if they're going under a certain speed. Because they hare a hazard if they are going too slow.

> trucks are required to put their flashers on if they're going under a certain speed.

This is not correct. Many states in the US do not allow the use of hazard lights while moving.

Any moving vehicle is a hazard, the faster it's moving (relative to the road) the greater the hazard

A stopped car won't crash. A moving car will.