Wed February 01, 2012 By:

all convex lenses are convergent lenses but all convergent lenses are not convex lenses. why?

Expert Reply
Wed February 01, 2012
Actually the nature of lens ( convergent or divergent ) depends on the shape of the lens as well as the refractive index of the lens material and the medium in which it is placed.
For example if you place a convex lens in a liquid which has the same refractive index as of lens , the lght will not refract at all and you will feel that there is no lens in the liquid , in the same way a divergent lens could work as a convegent lens depending that in which medium it is placed.
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