The Impossible Domino

I show you a domino that stands back up after falling over and hitting the domino next to it.

[midobo]

Wow. I've set up dominoes for 23 years now and learned something new today.

[aaronjamt]

Came back just to say that it feels like quite a coincidence that The Action Lab and Mark Rober just uploaded domino-themed videos within the span of a few hours. Coincidence? I think not!

[Hevesh]

it’s cool how when the second domino falls, it turns into a lever with that extra ridge, and can just spring up the first domino again! really interesting concept and great explanation. dominoes that are bottom-heavy indeed are easier to stand up.

[VideoSage]

"Impossible dominos aren't that impossible...."
Long as you only have 2.

[cardinalhamneggs]

I really like how this works. Because physics, the domino won’t have enough energy to return to its stable upright state, but it doesn’t _have_ to because it’s designed specifically to have enough energy to reach an _unstable_ position where, once reached, it will automatically settle into its fully upright position due to its low center of gravity.

[christmassnow]

Next challenge: How many dominos in a row can make an "impossible" domino?

[cheeto]

I was thinking he was just going to stick a bunch of "Weeble Wobbles" in a row.

[dannycamacho]

Honestly was expecting a long line of dominos testing this still a good video

[thom]

People want to see a whole row of them doing that... only problem is: those two are different from each other in mass and center of gravity, so they're not even dominos at that point. How about set a bunch of those pairs up in sequence so that every other one will return back up?

[tianamatson]

it is impossible to have a row of dominos pop back up again.

[gandhibapu]

Mom: he must be studying hard for his upcoming exam

Me at 3 am: 1:06

[Glamerth]

My professor on zoom: “Thanks for paying attention everyone”
Me:

[shadykermit]

Dominos cannot tip themselves back up
Action Lab: Or can they?

*Vsauce theme intensifies*

[buddhists]

*He says dominos like he thought of 101 Dalmatians mid-sentence.*

“Dolminoles”

[EvanOfTheDarkness]

TL DR: The second domino is designed to give some of the kinetic energy is has to the first domino when it hits the ground. The hollow top and bottom is not really important, it just makes the second domino store more potential energy than the first, despite being the same material, so it takes less energy to upright the first domino.

[eeveelovereve]

Whoah I've never seen an Action Lab video so fresh

[eeveelovereve]

When the dominos were just falling over like normal instead of popping up like he hoped, *I felt that*

[Mike__B]

In a world where everything that tips over is a "domino"

[contagiousingenuityagency]

James,

Here's something I noticed at 1:29. The domino with the big hole through it has its long sides acting much like springboards.
When it hits the other domino (on the left of the screen) the impact lands around 2/3 down from the top of the long hole (visually), compresses the 'wall' of the domino on the right and springs it backwards.
That in my opinion is the momentum which caused it to flip the other way.


Hope at least some of this makes any sort of sense :)

[GamerX-]

All I was waiting for was him to realize you just needed weights on the bottom. The problem is like those old toys that were in an egg shape and had a ton of weight on the bottom and the top weighed nothing so that as long as you weren’t holding it and it was set down it would always stand up.