I believe traffic “moves” backwards around 12mph? So if someone slams on their brakes, it creates a ripple effect that is seen backwards at that rate, so you can calculate the distance/time of traffic to estimate when and where some incident occurred, even when there’s nothing there.
I believe traffic “moves” backwards around 12mph? So if someone slams on their brakes, it creates a ripple effect that is seen backwards at that rate, so you can calculate the distance/time of traffic to estimate when and where some incident occurred, even when there’s nothing there.
Sounds like you’re describing a shockwave traffic jam.
That’s the one! I forgot the name for it — thanks!