So it's just a new circle? That's great! I'm serious; it really made the actual problem a lot easier now. Actually I thought it would be some sort of shape that looked like a circle, but I wasn't sure whether it was a new circle equation or if it was more complex ... anyway, thanks.

And oh, the equation of a circle, just a little mistake writing $\displaystyle vt$ instead of $\displaystyle v^2t^2$... hehe.

I guess it's difficult to derive the fact that it will just remain the equation of a circle. Anyway, I have to try to derive it! Maybe I’ll put the derivation here if I succeed to make it.