An achromatic combination of lenses is to be made by using a convex and a concave lens. The two lenses should have

An achromatic combination of lenses produces

An achromatic combination of lenses is formed by joining

An achromatic combination of lenses is formed by joining

Compare convex and concave lenses

Explain various types of convex and concave lenses.

The dispersive powers of the materials of two lenses forming an achromatic combination are in the ratio of 4:3 . Effective focal length of the two lenses is + 60 cm then the focal lengths of the lenses should be

Show that the power of the achromatic combination of two convex lenses of the same material is equal to the mean power of the lenses.