Question

explain basic assumption in machanics​

Answer 1

The fundamental assumption of statistical mechanics is that, over time, an isolated system in a given macrostate is equally likely to be found in any of it's microstates. Thus, our system of 2 atoms is most likely to be in a microstate where energy is split up 50/50....

Answer 2

Each particle can be subdivided into molecules, atoms and electrons etc. It is not feasible to solve an engineering problem by treating a body as a conglomeration of such discrete particles. The body is assumed to consist of a continuous distribution of matter. In other words, body is treated as continuum.

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