# How Dominoes Work

A domino is a small rectangular block, either wooden or plastic, that has a line down its center that separates each end into squares. These squares are blank or marked with numbers that resemble those on dice. Dominoes are used much like playing cards or dice to play a variety of games. The most common are positional games, in which players take turns placing one domino edge to edge against another so that the adjacent sides have matching values or form some specified total. There are many variations of these games. Some of them are very simple, while others can be quite complex.

Dominoes are also used to create beautiful artworks by arranging them in straight and curved lines. They can also be set up in 3-D arrangements and used as an aid for physics demonstrations. Lily Hevesh started collecting and building dominoes at age 9. She became a professional domino artist at the age of 20, creating stunning setups for movies, TV shows, and events. Her YouTube channel, Hevesh5, has more than 2 million subscribers.

Hevesh uses a variety of tools in her work, including a drill press, radial arm saw, scroll saw, belt sander, and welder. However, she explains that her favorite tool is the one in her grandmother’s garage: a simple, manual woodworking saw. Her process is simple and focuses on precision. She makes several test versions of each section before completing the entire installation. This allows her to make precise adjustments and ensure that everything will work correctly.

As she works, Hevesh explains the physics behind her creations. She says that the first domino she sets up will remain upright unless a force, such as gravity, causes it to fall over. When that happens, it gives the other dominoes that are still standing a push to fall over as well. This is what creates the chain reaction that results in domino after domino toppling over.

Physicist Stephen Morris says that a domino’s potential energy is based on its position. When a domino is upright, it has stored energy, but when it falls over, much of that energy is converted into kinetic energy that causes other dominoes to fall over as well.

The domino theory is often used to describe the effect of one event on another, such as when an earthquake triggers a tsunami that affects neighboring countries. It has been used by politicians to justify foreign policy decisions, such as the United States’ support for the Ngo Dinh Diem regime in South Vietnam and of non-communist forces fighting communist rebels in Laos in the 1960s. Richard Nixon, in the 1977 Frost/Nixon interviews, defended his actions on the basis of the domino theory.