Bear with me, I am mathematically challenged chemist. I am trying to understand following situation: There are two masses connected with a line. They rotate about an axis perpendicular to the line. System have some easy to calculate angular momentum. In a closed system angular momentum is constant, so as long as we don't touch it, angular momentum is not changing. Line breaks. Now we have two masses going in straight lines. Obviously at the moment line broke each mass had some linear momentum and it still has the same linear momentum, tangential to the previous trajectory. However, I can't see what have happened to the angular momentum. L=rxp - r and p vectors are getting parallel, so the cross product becomes zero. I suppose I am mising something simple, but I can't see it :grumpy: The only explanation I can think of is that angular momentum conservation is only kind of emergent property of the rotating system, while linear momentum conservation is the 'real' principle, but I feel like that's rather a bold statement.