Question
In optical instruments, the lenses are used to form images by:

Answer

  1. Refraction
Explanation:
A lens is a piece of glass (plastic) with two refracting surfaces, which are either curved (e.g., a segment of a sphere) or plain.
Lenses are used to form images by refraction in optical instruments (microscopes, telescopes, cameras, etc.)
There are two types of lenses: converging (thickest in the middle) and diverging (thickest at the edges).

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