Chapter 9 – Ray Optics

Two identical glass (μg=3/2) equiconvex lenses of focal length f are kept in contact. The space between the two lenses is filled with water (μw=4/3). The focal length of the combination is Two identical glass (μg=3/2) equiconvex lenses of focal length f are kept in contact. The space between the two lenses is filled with [...]

The radius of curvature of the convex face of a plano-convex lens is 15 cm and the refractive index of the material of the lens is 1.4. Then, the power of the lens in dioptre is the power of the lens in dioptre is The radius of curvature of the convex face of a plano-convex [...]

Two plano-concave lenses (1 and 2) of glass of refractive index 1.5 have radii of curvature 25 cm and 20 cm. They are placed in contact with their curved surface towards each other and the space between them is filled with liquid of refractive index 4/3. Then the combination is The focal length of a [...]

The focal length of a convex lens is 10cm and its refractive index is 1.5 is placed in liquid of refractive index 1.25 then its focal length will be The focal length of a convex lens is 10cm and its refractive index is 1.5 is placed in liquid of refractive index 1.25 then its focal [...]

What is the refractive index of material of a planoconvex lens, if the radius of curvature of the convex surface is 10 cm and focal length of the lens is 30 cm ? if the radius of curvature of the convex surface is 10 cm and focal length of the lens is 30 cm ? [...]

A students plots a graph between inverse of magnification 1/m produced by a convex thin lens and the object distance u as shown in figure. What was the focal length of the lens used? A students plots a graph between inverse of magnification 1/m produced by a convex thin lens and the object distance u [...]

A hollow double concave lens is made of very thin transparent material. It can be filled with air or either of two liquids L1 or L2 ​having refractive indices μ1 ​and μ2 respectively (μ2 > μ1 ​> 1). The lens will diverge a parallel beam of light if it is filled with Which one of [...]

A concave lens of glass, refractive index 1.5, has both surfaces of same radius of curvature R. On immersion in a medium of refractive index 1.75, it will behave as a : A concave lens of glass has both surfaces of same radius of curvature R. On immersion in a medium of refractive index 1.75 [...]

Which one of the following spherical lenses does not exhibit dispersion? The radii of curvature of the surfaces of the lenses are as given in the diagram. Which one of the following spherical lenses does not exhibit dispersion? The radii of curvature of the surfaces of the lenses are as given in the diagram. November [...]

A point source of light is kept below the surface of water (nw = 4/3) at a depth of root 7 m. The radius of the circular bright patch of light noticed on the surface of water is ______ m. A point source of light is kept below the surface of water (nw = 4/3) [...]