Something I’ve always wondered about, why does the increase in volume of cars on a road cause the speed to decrease. Is there just this one guy who drives real slow everyday and holds everyone up or what?
Ideally, you want to drive such that the distance between you and the next car is greater than your stopping distance. As your speed goes up, your stopping distance goes up. If the density of cars is high, then the distance between you and the next car is low, so you have to bring your speed down to compensate.
1.) As you mentioned, the chain reaction effect.
2.) Any given road (system) can only handle so much traffic (throughput).
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