Rigid-body domino chain reaction with realistic physics. Watch the wave of falling dominoes propagate through carefully arranged patterns, transferring energy from piece to piece.
Rigid body dynamics with contact constraints, friction and momentum transfer. The "domino wave" propagates faster than any individual piece falls.
Watch the chain reaction unfold. Experiment with different arrangements and spacing to see how wave speed changes.
A domino can topple a piece 1.5× larger than itself. Starting from a 5mm domino, just 29 progressively larger pieces could topple a domino as tall as the Empire State Building!
This simulation models a rigid-body domino chain reaction using real physics equations. Each upright tile, once toppled by gravity, transfers its kinetic energy and angular momentum to the next tile in the sequence, creating a self-sustaining wave of falling pieces that spreads along the entire line. Users can observe how spacing, tile height, and arrangement affect the speed and success of the propagating wave.
Domino chain reactions are a classic demonstration of momentum transfer and wave propagation, and the same underlying physics appears in nuclear fission cascades, neural signal propagation, and mechanical relay systems used in engineering.
A domino chain reaction is a process where one falling tile transfers enough energy to topple the next, which then topples the one after it, creating a continuous cascade. The energy source is gravitational potential energy stored in each upright tile. Once the first tile is pushed past its tipping point, the chain becomes self-sustaining without any further external force.
Click anywhere on the canvas to place individual domino tiles, or use the "Draw line" button to automatically fill a straight row at the current spacing. Adjust tile height and spacing with the sliders, then press "Launch!" to topple the first tile and watch the chain reaction unfold. Use "Slow / Speed up" to switch to slow-motion and observe the momentum transfer in detail, and "Clear all" to reset and try a new arrangement.
Each domino only needs to rotate a small fraction of the way before its top edge reaches the next tile and begins pushing it. Because each tile starts falling almost immediately after the previous one contacts it, the wave front advances along the line much faster than any individual tile completes its full fall to the ground. This is a key feature of domino waves: wave speed and individual tile fall time are independent quantities.
A falling domino rotates about its base edge, so its angular acceleration is governed by the torque of gravity about that pivot: dω/dt = (g / r) * cos(θ), where ω is angular velocity, θ is the tilt angle from vertical, g is gravitational acceleration (9.8 m/s²), and r is the radius of gyration. When a falling tile's top edge contacts the next tile, angular momentum is transferred with some loss to friction and deformation, roughly: ω_next = k * ω_falling, where k is typically between 0.5 and 0.7 depending on tile geometry and spacing.
A domino can topple a tile approximately 1.5 times its own height, because the falling tile's center of mass sweeps a large arc and delivers more energy than the upright tile has stored. This amplification means that a sequence of progressively larger tiles can grow enormously: starting from a 5 mm domino, just 29 tiles each 1.5 times taller than the previous one would produce a final tile as tall as the Empire State Building (443 m). This exponential scaling is used in mechanical amplifier demonstrations in engineering education.
Yes — the wave speed depends on tile height, thickness, and spacing. Taller tiles store more potential energy and can reach adjacent tiles sooner, increasing wave speed. Wider spacing requires each tile to rotate further before contacting the next, reducing speed. Studies have measured domino wave speeds ranging from roughly 0.5 m/s to over 2 m/s depending on configuration. In this simulation, you can observe these effects directly by changing the spacing and height sliders before launching.
The physics of domino chains was first rigorously analyzed by Jearl Walker, a physicist known for popularizing physics demonstrations, in the 1980s. A landmark 1983 paper by Shaw quantified the amplification ratio and wave speed. Later work by Stronge and Shu (1988) provided exact analytical solutions for the energy transfer between tiles. These studies turned a classic toy into a well-understood model of mechanical cascade systems.
The domino cascade is a physical analogy for many real-world chain reactions. Nuclear fission uses neutrons instead of mechanical momentum — one fission event releases neutrons that trigger neighboring nuclei. Neuronal action potential propagation along a nerve fiber is another direct analogy, where one depolarized cell triggers the next. Financial contagion, where one bank failure causes others to fail, is a socioeconomic parallel. All share the key property: each element stores energy that is released and partially transferred to neighbors.
Mechanical relay chains based on the domino principle are used in safety interlocks, where a small trigger force must reliably initiate a large mechanical action. In microelectromechanical systems (MEMS), cascaded bistable elements can store and release energy in sequence for actuators and logic gates. Explosive chain initiators in pyrotechnics and mining use the same cascade principle to propagate a detonation signal reliably from a low-energy initiator to a main charge.
Current research explores domino cascades in 3D arrangements, curved paths, and branching networks where the wave must split or merge. Researchers are also studying cascades of non-uniform tiles to design systems with programmable wave speeds or stopping conditions. At the micro-scale, domino-inspired mechanical logic gates are being investigated for computing without electronics. At the macro-scale, domino models are used in earthquake fault rupture propagation studies to understand how slip on one fault segment can trigger adjacent segments.