Information AboutInertial |
| CATEGORIES ABOUT INERTIAL FRAME OF REFERENCE | |
| frames of reference | |
| classical mechanics | |
| introductory physics | |
| relativity | |
| astrodynamics | |
|
INTRODUCTION In Physics , an object has inertial motion if no external forces are being applied to it, famously stated as Newton's First Law Of Motion . When such an object’s state of motion is extrapolated over a region of space to take in all other possible objects in the region with the same state of motion, and these are used to define a common Coordinate System , this system is referred to as a '''frame'''. USE OF INERTIAL FRAMES Inertial frames of reference are relevant to Newtonian Relativity and Einstein 's Special Theory Of Relativity .
TRANSFORMATIONS The way that nominal distances and times are converted from one coordinate system to another is referred to as a Transformation . In classical mechanics the Kinetic Energy of a system depends on the inertial frame of reference. It is lowest with respect to the Center Of Mass , i.e., in a frame of reference in which the center of mass is stationary. In another frame of reference the additional kinetic energy is that corresponding to the total mass and the speed of the center of mass. Einstein argued that if we only assume that light propagates at ''c'' in a single Preferred Frame (i.e., if we assume an absolute fixed aether, Classical Theory ), transformation of space and time coordinates is performed using Galilean Transformation s, whereas with special relativity we obtain Lorentz Transformation s, which only coincide with the earlier results for relative velocities that are reasonably small in comparison with the speed of light. EINSTEIN’S GENERAL THEORY OF RELATIVITY Einstein’s General Theory modifies the distinction between nominally "inertial" and "noninertial" effects, by replacing special relativity's "flat", Euclidean geometry with a curved Non-Euclidean metric. In general relativity, the principle of inertia is replaced with the principle of Geodesic Motion , whereby objects move in a way dictated by the curvature of spacetime. As a consequence of this curvature, it is not a given in general relativity that inertial objects moving at a given rate with respect to each other will continue to do so. This phenomenon of Geodesic Deviation means that inertial frames of reference do not exist globally as they do in Newtonian mechanics and special relativity. However, the general theory reduces to the special theory over sufficiently small regions of spacetime, where curvature effects become less important and the earlier inertial frame arguments can come back into play. Consequently, modern SR is now sometimes described as only a “local theory”. (However, this refers to the theory’s application rather than to its derivation.) EXTERNAL LINKS REFERENCES
|
|
|