出典:Wikipedia
出典:『Wikipedia』 (2011/05/26 00:52 UTC 版)
Rest in physics refers to an object being stationary relative to a particular frame of reference or another object. According to the theory of relativity it is said that an object is: at rest relative to another. For example, a train decelerates on approach to a station and eventually stops alongside the platform. The train can be said to be at rest with respect to the station or just at rest, since in practice we do not need to specify the frame of reference if it is obvious from the context.