A plano convex lens is made of glass of refractive index 1.5. The radius of curvature of its convex surface is R. Its focal length is

A plano-convex lens is made of glass of refractive index 1.6. the radius of curvature of its curved surface is 30 cm. What is the focal length of the lens ?

A plano-concave lens is made of glass of refractive index 1.5 an the radius of curvature of its curved surface is 50 cm. What is the power of the lens?

A plano-convex lens is made of refractive index 1.6. The radius of curvature of the curved surface is 60 cm. The focal length of the lens is

A plano-convex lens is made of refractive index 1.6.If the radius of curvature of the curved surface is 60 cm,then focal length of the lens is:

A concavo-convex lens is made of glass of refractive index 1.5. The radii of curvature of its two surfaces are 30 cm and 50 cm. Its focal length when placed in a liquid of refractive index 1.4 is

A concavo-convex lens is made of glass of refractive index 1.5. The radii of curvature of its two surfaces are 30 cm and 50 cm. Its focal length when placed in a liquid of refractive index 1.4 is

A plano-convex lens is made of material having refractive index 1.5. The radius of curvature of curved surface is 60 cm. The focal length of the lens is ______ cm.

A plano-convex lens is made of material having refractive index 1.5. The radius of curvature of curved surface is 60 cm. The focal length of the lens is ______ cm.