Simulating a Ball Rolling Down a Slope - HTML5 Canvas JavaScript

How can I simulate a ball rolling开发者_开发知识库 down a given slope using HTML5 canvas and JavaScript? Can someone provide code as to how to do this?

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This might not be exactly what you're looking for, but the defacto standard for javascript-based physics is called Box2DJS.

You can find it here: http://box2d-js.sourceforge.net/