Describe a physics experiment.Watch it actually happen.

Type a pendulum losing energy to air resistance and get a live simulation on a real engine — then reshape it with words, with sliders, or by grabbing it.

Free, and no API key needed to start.

Behind this text: three bodies under F = GMm/r², integrated live.Click a planet.

What people are building right now

Real experiments, published minutes or hours ago. Click through and watch any of them actually run.

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Falcon 9 to orbit: how a rocket works

@team7569 · 6d ago

0012

The inner solar system, to scale

@team7569 · 6d ago

009

The spring that remembers

@team7569 · 1mo ago

0029

A comet's tail

@team7569 · 1mo ago

0019

Two paths, one landing

@team7569 · 1mo ago

0025

The gold foil: finding the nucleus

@team7569 · 1mo ago

17101

Start with a sentence. Leave knowing why it happened.

For anyone learning this on their own, and for anyone who has to run the demo live in front of a room and needs it to behave the same way twice.