Question

What is a lens? what are they and their uses

Answer 1

A lens is a portion of spherical glass slab. There are two types:

Concave and convex

Uses of concave:

(1) Flashlights
(2)Telescopes and photography

Uses of convex:

(1) Microscopes and magnifying glasses
(2)Correction of hypermetropia

Thank you.

Answer 2

a lence is a portion of a transparent refracting medium bounded by two surfaces.
it is of two types:-
•convex lens
•concave lens

it is used for making

1) magnifying glass
2) microscope
3) telescope
4) photographic camera
5) they are also used in correction of eye defect i.e.myopia and hypermetropia.

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