Consider a collection of n rigid, massive bodies interacting according to their mutual gravitational attraction. A relative equilibrium motion is one where the entire configuration rotates rigidly and uniformly about a fixed axis in R. Such a motion is possible only for special positions and orientations of the bodies. A minimal energy motion is one which has the minimum possible energy in its ...

How do we judge an object's velocity when we ourselves are moving? Subjects compared the velocity of a moving object before and during simulated ego-motion. The simulation consisted of moving the visible environment relative to the subject's eye in precisely the way that a static environment would move relative to the eye if the subject had moved. The ensuing motion of the background on the scr...

Two spaceships, A and B, are in motion relative to each other. Their motion relative to the empty space they are in is undefined and undefinable. We can consider ship A to be stationary relative to space and ship B to be moving or vice versa. The two situations are entirely equivalent. Each ship’s motion relative to the other is symmetric. Relative to a clock in either ship, an identical clock ...

This paper has explained that, the motion can be divided into two types, i.e. relative motion between two objects and circular motion unrelated to relative motion (also known as absolute motion). Time delay resulted from relative motion is referred to as relative time delay; time delay caused by circular motion is referred to as absolute time delay. Relative time delay refers to a time delay ef...