HTML5 Canvas: Interactive Ball Physics Example

Hello guys! I've been really sharpening up my HTML5 Canvas skills and I created this neat little example bundling key physics concepts and user interactivity inside canvas. I will have a tutorial very soon explaining line by line the code behind this example as well as key concepts to remember. In the tutorial, I will also talk about some of the things I struggled with and break them down so you guys can understand. You can grab and drag the ball and sort of toss it around to see how it interacts with the walls. You can also pause the simulation using the Pause button below. Please make sure to enable JavaScript. Enjoy the example!
PS: There does seem to be an issue sometimes with the mouse events but you can refresh the page to fix this.