How to use it
Press Pull 1 ball (or click the end ball) to lift and release it — it swings in, clicks, and sends the far ball flying out, back and forth with a satisfying rhythm that slowly settles. Pull 2 to launch two at a time. Re-pull any time to keep it going.
Private by design. Just an animation and synthesized clicks — nothing is recorded or uploaded.
Frequently asked questions
How does a Newton's cradle work?
A lifted ball strikes the row and its momentum passes through the still balls to launch the one at the far end. Lift two, two fly out — momentum and energy are conserved.
Why is there no sound?
Browsers start audio only after you interact. Pull a ball and check your device isn't muted.
Is it real physics?
It's a faithful animation with a click on each collision and a slow energy decay, not a full physics solver — but it captures the rhythm.
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