Question

A point object is placed in air at a distance of 4R on the principal axis of a convex spherical surface of radius of curvature R separating two mediums, air and glass. As the object is moved towards the surface, the image formed is :

A point light source rests on the bottom of a bucket filled with a liquid of refractive index μ = 1.25 up to height of 10 cm. Calculate : (a) the critical angle for liquid-air interface (b) radius of circular light patch formed on the surface by light emerging from the source.

A ray of light is incident on a surface separating air from a denser medium A of refractive index μ₁. It is then made incident on the parallel surface of another medium B of refractive index μ₂ at the same angle of incidence. If the angle of refraction in the two media are 30° and 35° respectively, then in which one of the two media (A or B) will light travel faster and why ?

What are the two main considerations for designing the objective and eyepiece lenses of an astronomical telescope ? Obtain the expression for magnifying power of the telescope when the final image is formed at infinity.