How do I simulate a yo-yo?

Open this page and use the live Collision Lab tool below — set your inputs and the simulation runs instantly in your browser using real numerics. No install, no account needed.

Yes. The simulation runs free in your browser. A one-time unlock or a Pro plan adds advanced parameters, saved presets, data import, and clean exports.

Can I use my own numbers?

Absolutely — every input is adjustable, and with data import you can drive a yo-yo from your own measurements.

Use case · powered by Collision Lab

Collision Lab for a yo-yo

Simulate a yo-yo live in your browser. This runs the real Collision Lab solver — adjust the inputs, watch it respond instantly, and export the result. No install, no account.

For:Students Researchers Educators Engineers Hobbyists & Makers K-12 Students First Responders

Collision Lab (1D)Live

momentum is always conserved

Controls

Presets

Mass 1 (kg)

Mass 2 (kg)

Velocity 1 (m/s)

Velocity 2 (m/s)

Restitution e

Momentum is conserved in every collision. Kinetic energy is conserved only when e=1 (perfectly elastic); at e=0 the carts stick together and the lost energy becomes heat and sound. Drag either cart on the canvas to set where it starts.

▶ Run in Python

Data Inspector

Final v₁0.33 m/s

Final v₂4.33 m/s

KE before9.5 J

KE after9.5 J

Energy lost0%

Governing equation

v_{1}^{'} = \frac{m _{1} u _{1} + m _{2} u _{2} - m _{2} e ( u _{1} - u _{2} )}{m _{1} + m _{2}} = 0.33, v_{2}^{'} = \frac{m _{1} u _{1} + m _{2} u _{2} + m _{1} e ( u _{1} - u _{2} )}{m _{1} + m _{2}} = 4.33

Reading this result: This collision is elastic (e=1), so kinetic energy is fully conserved; momentum-sharing only redistributes the speeds between the two masses.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

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About this simulation

The full Collision Lab tool models a yo-yo with the same numerics engineers and scientists use — running entirely client-side. Change any parameter and the result updates in real time, so you can build intuition, check a design, or teach the concept without spreadsheets or installs.

More you can do with Collision Lab

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Other ways to simulate a yo-yo

Particle / N-Body for a yo-yo Heat & Wave Fields for a yo-yo GPU Compute (WebGPU) for a yo-yo WebGPU Fluid for a yo-yo GPU N-Body for a yo-yo GPU PDE Solver for a yo-yo

Frequently asked questions

How do I simulate a yo-yo?: Open this page and use the live Collision Lab tool below — set your inputs and the simulation runs instantly in your browser using real numerics. No install, no account needed.
Is it free?: Yes. The simulation runs free in your browser. A one-time unlock or a Pro plan adds advanced parameters, saved presets, data import, and clean exports.
Can I use my own numbers?: Absolutely — every input is adjustable, and with data import you can drive a yo-yo from your own measurements.