A domino can knock over the next domino at about 1.5x larger (perhaps 2x larger) and this instant video classic from 2009 is a great example of this chain reaction. Watch University of Toronto’s Professor Stephen Morris knock over a 1-meter tall domino that weighs over 100 pounds by starting with a 5mm high by 1mm thick domino. TINY.

There are 13 dominoes in this sequence. If Professor Morris used 29 dominoes in total, with the next one always being 1.5x larger, the last domino would be the height of the Empire State Building.

There are more chain reactions and many, many physics videos in the archives. 

via Physics Buzz.