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Mirrors and Lenses

Nearly all the methods used in optical measurements are indirect. The quantity required is deduced by calculation from the quantities actually measured, or the law to be demonstrated is inferred from the observations made by a process of reasoning. This is illustrated by the following experiment on the law of reflexion and by the experiments on focal lengths. The law of refraction may also be verified by the measurements of the refractive index of a transparent medium.

Last Update: 2011-03-15