model (physical)

A physical model is used in various contexts to mean a physical representation of some thing. That thing may be a single item or object (for example, a bolt) or a large system (for example, the Solar System).The geometry of the model and the object it represents are often similar in the sense that one is a rescaling of the other; in such cases the scale is an important characteristic. However, in many cases the similarity is only approximate or even intentionally distorted. Sometimes the distortion is systematic with e.g. a fixed scale horizontally and a larger fixed scale vertically when modelling topography of a large area (as opposed to a model of a smaller mountain region, which may well use the same scale horizontally and vertically, and show the true slopes).
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