Ray Optics Test...

When a ray of light enters a medium of refractive index µ, then it is observed that the angle of refraction is half the angle of incidence. The value of angle of incidence will be

An under water swimmer is at a depth of 12 m below the surface of water. A bird is at a height of 18 m from the surface of water, directly above his eyes. For the swimmer, the bird appears to be at a distance X from the surface of water. (Refractive index of water is 4/3). The value of X is

Fraunhofer spectrum is a

An equilateral prism is placed on the prism table of a spectrometer in the position of minimum deviation. If the angle of incidence is 60º, the angle of deviation of the ray is

Three glass prisms A, B and C of the same refractive index are placed in contact with eachother as shown in Fig with no air gap between the prisms. A monochromatic ray of light OP passes through the prism assembly and emerges as QR. The condition of minimum deviation is satisfied in the prism.

A ray falls on a prism ABC (AB = BC) and travels as shown in Fig. The minimum refractive index of the prism material should be

In a thin prism of glass g (a_µg = 1.5) , which of the following relations between the angle of minimum deviation δ_m and angle of refraction r will be correct?

If a monochromatic green light is incident on a phosphorescent substance, the colour of light emitted by it is

A ray of light is incident at an angle of 60º on one face of a prism of angle 30º. The emergent ray of light makes an angle of 30º with incident ray. The angle made by emergent ray with second face of prism will be

Two lenses in contact form an achromatic lens. Their focal lengths are in the ratio 2:3. Their dispersive powers must be in the ratio of