Question

Q.... what is concave and convex lens????

Answer 1

The lens which is thin on the cornor and thik in the middle imis called convex and tge lens which is thick on the cornor but thin in the middle is called concave

Answer 2

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Concave Lens :-
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A concave lens is a lens that possesses at least one surface that curves inwards.

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Convex Lens :-
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A convex lens is a lens that converges rays of light that are traveling parallel to its principal axis.