Domino Chain Reaction (geometric growth in action)

A domino can knock over another domino about 1.5x larger than itself. A chain of dominos of increasing size makes a kind of mechanical chain reaction that starts with a tiny push and knocks down an impressively large domino.

Original idea by Lorne Whitehead, American Journal of Physics, Vol. 51, page 182 (1983).

See
for sophisticated discussions of the physics.

As seen on QI in the "kinetic" episode. I was contacted by those Elves.

[kabishen]

Okay, so when's the video with 29 dominoes coming?

[Captain_Irk]

"If I had 29 dominoes, the last one would be as tall as the empire state building"

Terrorism gone dominoes?

[baileybrown]

0:55 when you're trying to poop quietly in a public bathroom but it splashes too loud.

[Mercylessgood]

A good metaphor for life challanges and creating small wins just like dominos .

[MCO]

That retirement commercial brought me here!!

[paullangton-rogers]

That's incredible. Something so simple but you don't realize the latent power in this. I just received an e-mail from life coach guru Brian Johnson who mentioned this domino effect and he compares it to achieving your full potential in life by lining up your domino's correctly (goals) starting with smallest micro-goal. That's what brought me here!! Pretty powerful and inspiring stuff.

[smorris]

It is a common question. The energy released is just some fraction (less than 100%) of the energy that you needed to expend to lift the dominos into place. So there is no net gain of energy to be harnessed.

[tfwhackyengineer]

"Give me a domino and I shall knock over the world." ~Archimedes

[haroldwiferton]

As an older man I've seen a lot of things get pushed over, on, around and thru, why just the other day one of the nursing staff pushed me down the hall in my wheel chair since they took my scooter for running over people.  I know all about being pushed around because I'm older and wiser than you.  Moderator of /r/oldfartz       * tips old wrinkly fedora *

[distantlands]

It's obviously a trick by Russian hackers designed to make the democrats lose!

[smorris]

All dimensions are scaled by 1.5; the height, width and thickness. So the volume changes by (1.5)^3.

[justicewarrior]

First time I understood compound investment!!
This is how Warren Buffet made his billions!
Thank you

[DaveGamesVT]

That first tiny domino is me going "Maybe instead of going to sleep, I stay up and watch a video about dominoes!"

[Sawaelo]

Now I wanna see the last domino being big enough that an adult human couldn't push it over :D
But a baby could start the chain reaction!

[nextlevelwarrior]

100 lbs?! you lifted that with finger grip like it was nothing

[PacoOtis]

Great! Thanks! As a retired instructor it is great to see someone like you as it is obvious you know what you are doing and present it quite well.

[SsehKalai]

For the record, as was asked before Google comments came in, a procession of 60 dominoes, the last would be 122, 560km high, only slightly under 1/3 of the way to the moon.

[smorris]

Yes. I placed them apart a distance equal to their width, so of course than length is also scaled by 1.5 each step.

[smorris]

I believe I used a spacing equal to the width, which is half the height. Every dimension, including the spacing, should scale by the same factor from one stage to the next. I did not make a detailed study.

[blueskyredkite]

If this guy was ever your teacher you were very lucky. Teachers with this kind of ability to are rare. He's worth his weight in gold. God bless you Stephen Morris.