How fast a row of dominoes topples depends on friction

Computer simulations reveal the physics behind the blocks’ cascades

I curved line of falling dominoes, toppling on each other.

A line of dominoes standing on end collapses in a chain reaction after the first one is knocked over. Computer simulations reveal that friction plays an important role in determining how fast the toppling cascades.

Martin Barraud/OJO Images/Getty Images Plus

It may seem like fun and games, but understanding how dominoes topple isn’t child’s play.