Hi, I have a question about momentum. Is linear and angular momentum just special cases of a more general total momentum equation, or are each two independent equations. Is it possible for angular momentum to be converted into linear momentum, or are they two fundamentally different and non related ideas. The reason I ask is because I came acorss a paper from a somewhat shady website that said it was possible for there to be equal but not opposite reaction. The reason he state was becuase of what he called a general conservation of momentum, where he said the initial translational momnetum = the final translational momentum + the linear equivalent of the final angular momentum. He did this by stating that the angular momentum L is mv*l , where m is the mass, v is the velocity and l is the distance. He said if he divided the angular momentum by the lever arm l, he could get its linear equivelant, and use that in the momentum equation that i typed earlier. He uses this to show that linear momentum equation is just a special case of a more general momentum equation, and that its possible to make a machine that can propell itself forward with no external force outside, I think he claims so by some form of a rotatingwheel that converts angular momentum to linear momentum, but this sounds like a load of crap to me, maybe because he writes most people dismiss this arugment, but thats just me. http://montalk.net/newton/newtonmath.html this is his paper if you want to see what im talking about.