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I have got a bit stuck on some basic principles to do with the motion of a billiard ball, and was hoping someone could point me in the right direction! Assuming I have the linear velocity and angular velocity of a uniform billiard ball (with the centre of mass exactly in the middle), how do I go about calculating its position 'x' millisecs in the future? I have tried reading several sources, but keep getting confused :grumpy: .

For example, http://archive.ncsa.uiuc.edu/Classes/MATH198/townsend/math.html, this website discusses how the linear velocity and angular velocity change over time. However the angular velocity does not seem to be affecting the motion of the ball in the equations outlined. Is this because the way that angular velocity affects the motion of a ball (on a surface with friction, with gravity) is elementary so just not discussed?

So confused! Can a rolling ball's path take a curved trajectory (assuming its on a perfectly level surface) due to angular velocity? Or if the ball is rolling does that mean the angular velocity and linear velocity are in sync at that point, so will then only travel in a straight line, slowing gradually due to friction with the surface?

Sorry if I have butchered some of the terms above, but if any one could take the time to guide me in the right direction of understanding this topic I would be hugely thankful.

Skusey

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# Sliding/rolling billiard balls

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