Physics Guides

20 in-depth guides to the physics these games are built on — what gravity actually does, why momentum makes a character feel heavy, how a collision is resolved, and where arcade physics stops being accurate. Written for readers with no physics background.

Cornerstone guides

The long reads. Start here if you want the full picture.

Pillar guide

How Collision Physics Works

How games detect collisions, what a contact normal is, how impulses resolve an impact, and why stacks need the solver to run several times per step.

Pillar guide

How Friction Changes Gameplay

Why friction is the cheapest way to make two levels play differently, how static and kinetic friction differ, and how to handle low-grip surfaces.

Pillar guide

How Pendulum Physics Works

Why a pendulum's period depends on length but not on mass, what the small-angle approximation is, and how games use pendulums for timing puzzles.

Pillar guide

Physics Arcade Games on Mobile

How physics games adapt to touchscreens, why on-screen buttons belong outside the canvas, and what a phone's performance budget means for simulation.

How these guides are written

Every guide follows the same principles. Explain the relationship before the formula. Use the games on this site as worked examples, because a mechanic you have felt is easier to reason about than one you have only read. Say explicitly where arcade physics departs from the real thing.

Physics values in games are tuned for playability rather than accuracy — gravity here is chosen so a screen-height fall takes about a second, not set to 9.8 metres per second squared. The relationships are faithful, and relationships are what build intuition. Our fact-checking policy explains how physical claims are checked, and Real Physics vs Simplified Game Physics is an honest account of where the models stop.