41.

A, B and C are the parallel sided transparent media of refractive indices n₁ n₂ and n₃ respectively. They are arranged as shown in the figure. A ray is incident at an angle i on the surface of separation of A and B which is as shown in the figure. After the refraction into the medium B, the ray grazes the surface of separation of the madia B and C. Then, sin i equals to

           

• $\frac{{\mathrm{n}}_3}{{\mathrm{n}}_1}$

• $\frac{{\mathrm{n}}_1}{{\mathrm{n}}_3}$

• $\frac{{\mathrm{n}}_2}{{\mathrm{n}}_3}$

• $\frac{{\mathrm{n}}_1}{{\mathrm{n}}_2}$

A boat has green light of wavelength λ = 500 nm on the mast. What wavelength would be measured and what colour would be observed for this light as seen by a diver submerged in water by the side of the boat ? Given, ${\mathrm{n}}_{\mathrm{w}} = \frac{4}{3}$.

• Green of wavelength 376 nm

• Red of wavelength 665 nm

• Green of wavelength 500 nm

• Blue of wavelength 376 nm

Two beams of red and violet colours are made to pass separately through a prism of A = 60°. In the minimum deviation position, the angle of refraction inside the prism will be

• greater for red colour

• equal but not 30° for both the colours

• greater for violet colour

• 30° for both the colours

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

• 400 cm

• 200 cm

• 100 cm

• 50 cm

The wavelength of the light used in Young's double slit experiment is λ. The intensity at a point on the screen is I, where the path difference is $\frac{\mathrm{\lambda }}{6}$. IF I₀ denotes the maximum intensity, then the ratio of I and I₀ is

• 0.866

• 0.5

• 0.707

• 0.75

What is the minimum thickness of a thin film required for constructive interference in the reflected light from it ?Given, the refractive index of the film = 1.5, wavelength of the light incident on the film = 600 nm.

• 100 nm

• 300 nm

• 50 nm

• 200 nm

Critical angle for certain medium is sin^-1 (0.6). The polarizing angle of that medium is

• tan^-1 (1.5)

• sin^-1 (0.8)

• tan^-1 (1.6667)

• tan^-1 (0.6667)

The spectrum of an oil flame is an example for

• line emission spectrum

• continuous emission spectrum

• line absorption spectrum

• band emission spectrum

According to Einstein's photoelectric equation, the graph of KE of the photoelectron emitted from the metal versus the frequency of the incident radiation gives a straight line graph, whose slope

• depends on the intensity of the incident radiation

• depends on the nature of the metal and also on the intensity of incident radiation

• is same for all metals and independent of the intensity of the incident radiation

• depends on the nature of the metal

An electron is moving in an orbit of a hydrogen atom from which there can be a maximum of six transition. An electron is moving in an orbit of another hydrogen atom from which there can be a maximum of three transition. The ratio of the velocities of the electron in these two orbits is

• $\frac{1}{2}$

• $\frac{2}{1}$

• $\frac{5}{4}$

• $\frac{3}{4}$