The convex surface of a plano-convex lens is silvered and the radius of curvature of this surface is R. Find the focal length of the system:

The radius of curvature of the face of plano-convex lens is 12cm and its refractive index is 1.5 . If the plane surface of the lens is now silvered, then find the focal length of the lens.

An object is placed 1m in front of the curved surface of a plano-convex lens whose plane surface is silvered. A real image is formed in front of the lens at a distance of 120cm. Then, the focal length of the lens is

A piano convex lens acts like a concave mirror of 28 cm focal length when its plane surface is silvered and like a concave mirror of 10 cm focal length when its curved surface is silvered. The refractive index of the material of the lens is

The radii of curvature of both the surfaces of a convex lens are equal. One of the surfaces is made plane by grinding. What is the new focal power of the lens ?

The radius of curvature of curved surface of a thin plano-convex lens is 10 cm and the refractive index is 1.5 . If the plano surface is silvered, then the focal length will be.

The effective focal length of the lens combination shown in Fig. is -60 cm . The radii of curvature of the curved surfaces of the plano-convex lenses are 12 cm each and refractive index of the material of the lens is 1.5 . The refractive index of the liquid is : .