The focal length of a concave-convex lens of radii of curvature 5 cm and 10 cm is 20 cm. what will be its focal length in water ? Given `.^(a)mu_(w) = 4//3`.

The focal length of a concavo - convex lens of radii of curvature 5 cm and 10 cm is 20 cm.What will be its focal length in water (mu=4//3) ?

Radius of curvature of a concave mirror is 20 cm, then its focal length is ...... cm.

A plano-convex lens (mu = 1.5) has a curved surface of radiys 15 cm. what is its focal length ?

The radii of curvature of a double concave lens are 30 cm and 45 cm. What is its focal length in water ? [""_(a)n_(g)=1.5, ""_(a)n_(w)=4//3]

Calculate the focal length of a convex lens whose radii of curvature of two surfaces is 10cm and 15cm respectively and its refractive index is 1.5.

If the focal length of a double convex lens is 12 cm and radii of curvatures of faces are 10 cm and 15 cm respectively, what is the refractive index of the lens?

The radii of curvature of the surfaces of a double convex lens are 20 cm and 30 cm . What will be its focal length and power in air and water respectively ? Refractive indices for glass and water are 3//2 and 4//3 respectively.

If the convex lens of focal length 10 cm and a concave lens of focal length 50 cm are kept in contact with each other. What will be the focal length of the combination ?