514void

umm, like at sea level or something?

would something as massive as the earth fall at g or 2g towards the earth?

I would of thought that an objects angular momentum would be around an axis that went through the center of mass of the object. So when you say that angular momentum is conserved, you mean that both objects center of mass has angular momentum around the axis of the center of mass of both objects? and this is conserved? what about each objects angular momentum, is this considered in the calculation?

O, i'm just concerned with 2 objects, so do i pick a frame where the net momentum is 0? let us start out that both have 0 angular momentum. So any collision of the 2 objects will mean that each will have the exact opposite angular momentum as the other? (both objects have the same mass)

pick a point? for each object?

Ok, seems a bit strange if the rod is hit by the ball right on the front of the ball, I would of thought it would bounce straight back from where it came from without spinning, even if it hits the rod in the middle or near the end.

What happens if one of the objects gains angular momentum from the collision, like if a ball hits a rod near the end.

Is there loss of linear momentum of 2 objects in an elastic collision if the net angular momentum increases and vica versa?

but yes, there would be a velocity gain as a linear function of the radius regardless of relativistic mass direction. Relativistic mass increases exponentially with velocity. So it would be beneficial to have the rest mass mostly near the edge of the disks. Is there anything else I should consider?

I'm not so sure what happens. But I think that there is a warning against considering a change in any sort of structure of the object due to relativistic mass.

Ok, That makes me think that if relativistic mass is directional, then there would be no relativistic mass force on the center of the disk when it isn't accelerating. this sort of makes sense since if relativistic mass isn't directional, then a spinning disk would slow down and eventually stop spinning. If relativistic mass is directional, then is slowing an object easier than speeding it?

this is only true in only one reference frame. the reference frame would be spinning around the center of the disk, at the same angular velocity of the disk. spinning reference frames are sort of silly, since if the frame extends past a certain radius, it would be going FTL. Unless you propose some sort of spiral reference frame that has angular velocity that goes at the speed of light at infinity radius. This sounds sort of cool.

relative velocity of what?

unresolved as its isn't a clearly defined equation, so I could use it inappropriately.

I had a look for it: http://en.wikipedia.org/wiki/Center_of_mass_(relativistic) It seem like it is unresolved.