A beam of parallel rays is brought to focus by a planoconvex. A thin Concave lens of the same focal length is joined to the first lens. The effect of this is

A beam of parallel rays is brought to focus by a planoconvex lens. A thin Concave lens of the same focal length is joined to the first lens. The effect of this is

A beam of parallel rays is brought to focus by a planoconvex lens. A thin Concave lens of the same focal length is joined to the first lens. The effect of this is

A beam of parallel rays is brought to a focus by a plano-convex lens. A thin concave lens of the same focal length is joined to the first lens. The effect of this is

Concave lens : Negative focal length :: convex lens …………..

Concave lens:Negative focal length:: Convex lens:____.