The Spring Paradox

This spring paradox is actually an analogy for Braess's Paradox which is about traffic. The surprising behaviour of the springs when the blue rope is cut is just like how journey times can actually go down when you close a major road, even with the same number of journeys being made.

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[thomasrosebrough]

"or you could consider that I'm making a video about it so it's probably the counterintuitive answer"

This is why I love this channel

[MrYviandivi]

A "Hectocar" is my favourite unit of measure.

[FrankLeeMadeere]

"You're NOT stuck in traffic, you ARE traffic!"

[overrideFunction]

This is the opposite of click bait. Dragged me in with something simple yet cool, showed me that and then provided something even more complex and cool. Well done!

[cgibbard]

I heard from a Google developer at one point that Google maps already is acting as a hive mind in this sense, recommending routes based on what will improve the time for everyone.

[RealCivilEngineerGaming]

A hectocar sounds like a really uninspired late generation Pokemon name 😅 Great video, as I highway engineer I am ashamed to say I was completely unaware of this law!

[VidBint]

I would definitely take a longer route if it’s less congested, even if it takes a couple more minutes. It would just “feel” faster & less stressful that being single-file

[sntslilhlpr]

I've definitely done this while playing Cities:Skylines. Sometimes the best way to solve a traffic jam isn't by adding, but subtracting.

[eltondefrance]

Something to note to help explain this intuitively, glancing at the initial setup makes your brain equate the red rope with the bottom spring and the green with the top since they are next to each other respectively. However, when you look, the force pulling on the red rope is actually the top spring and the force pulling on the green rope (when the blue is cut, of course). So, the springs can pull the ropes to overlap which helps make the weight rising make sense

[magicalcapi]

"What'll happen if I cut the blue hope?"
Obviously explode. It's never the blue wire Steve, stay safe

[Abigail-huwf]

Fascinating! You can also explore the concept of resistance in traffic, via the introduction of nominal congestion charges. By adding a cost to the use of certain roads, you're essentially adding a resistor to a circuit. You're making the route less attractive without removing it, and thus changing the dynamics of the system.

[erict]

I, commonly, choose a slightly longer route to avoid traffic. I see quite a few people doing the same on my rush hour commutes. We don't like sitting in heavy traffic. It's just too stressful

[miserepoignee]

If you're trying to look it up, "Bray's" paradox is actually spelled "Braess's" paradox.

[crazycatnip]

Lesson learned: tiny taxi drivers cause the spring to go up when the blue rope is cut. You learn something new every day!

[Xenosplitter]

The remaining blue road bit could be used as a public-transit-only road. Having a transit option that is able to take the shortest amount of time (4+1+4) sees more people taking the bus (or a similar option), which frees up more cars to drive on the longer routes (11+4), boosting people throughput through the road system.

[macrozone]

Came for physics, stayed for game theory

[GNKT]

As someone who lives in a heavily traffic city, I can honestly say that I rather take the longer timed route but be driving without any traffic than take the quicker route but be stuck in bumper to bumper traffic!
I know that's not what this video is about, but since he brought it up, I wanted to chime in my personal preference.

[jsbarretto]

A physical analogy for the Nash Equilibrium! The reason that locally optimal systems are not necessarily globally optimal (see also: climate change and many other social problems).

[saumyacow]

There's a related effect called the Downs Thompson paradox. To the effect that the equilibrium speed of road traffic is determined by the average door to door time of the equivalent journey taken by public transport. In other words, if you have a city with a public transport network, speeding up public transport also speeds up the road network. So if you've got a city with congested roads, your best solution might be to speed up the trains, rather than simply widen those roads. (Yes, I'm thinking of you, Sydney).

[TacetCat]

"I'm making a video about it, so it's probably the counterintuitive answer."

Crap, he's onto me. No one tell my high school teachers (and some college professors).