Refraction through a Rectangular Glass Slab

Q.

Speed of light in vacuum is:

Q.

What is lateral displacement? Draw a ray diagram showing the lateral displacement of a ray of light when it passes through a parallel sided glass slab.

Q.

The angle of incidence is equal to the angle of refraction

1. True
2. False

Q.

Velocity of light in glass whose refractive index with respect to air is 1.5 is $2\times {10}^8{ms}^{-1}$ and in certain liquid the velocity of light found to be $2.5\times {10}^8{ms}^{-1}$ .The refractive index of the liquid with respect to air is

1. 0.64
2. 0.8
3. 1.2
4. 1.44

Q.

A ray of light passes from a medium X to another medium Y. No refraction of light occurs if the ray of light hits the boundary of medium Y at an angle of : (a) $0^{\circ }$(b) ${45}^{\circ }$ (c) ${90}^{\circ }$ (d) ${120}^{\circ }$

Q.

A ray of light is incident normally on a plane glass slab. What will be (i) the angle of refraction, and (ii) the angle of deviation for the ray?

Q.

(a) With the help of a diagram, show how when light falls obliquely on the side of a rectangular glass slab, the emergent ray is parallel to the incident ray. . (b) Show the lateral displacement of the ray on the diagram. (c) State two factors on which the lateral displacement of the emergent ray depends.

Q.

A ray of light travelling in water falls at right angles to the boundary of a parallel-sided glass block. The ray of light : (a) is refracted towards the normal (b) is refracted away from the normal (c) does not get refracted (d) is reflected along the same path.

Q. A prism ABC (with BC as base) is placed in different orientations. A narrow beam of white light is incident on the prism as shown in figure. In which of the following cases, after dispersion, the third color from the top corresponds to the color of the sky?

1. 
2. 
3. 
4. 

Q.

Initially, an object is kept at a distance of $10cm$ from the convex lens and a sharp image is formed at $10cm$ ahead of the lens on the screen. Now a glass plate of$\mu =1.5cm$ and thickness$1.5cm$ is placed between object and lens. The distance by which the screen be shifted to get a sharp image on the screen will be:

1. $1.1cm$

2. $0.55cm$ away from the lens

3. $0.55cm$towards the lens

4. $5cm$

Q.

In the adjacent diagram, AO is a ray of light incident on a rectangular glass slab.

(a) Complete the path of the ray till it emerges out of the slab.

(b) In the diagram, mark the angle of incidence (i) and the angle of refraction (r) at the first interface. How is the refractive index of glass related to the angles i and r ?

(c) Mark angle of emergence by the letter e. How are the angles i and e related ?

(d) Which two rays are parallel to each other ?

(e) Indicate in the diagram the lateral displacement between the emergent ray and the incident ray. State one factor that affects the lateral displacement.

Q.

A beam of light travelling in a rectangular glass slab emerges into air. Draw a ray-diagram indicating the change in its path.

Q.

Draw a labelled ray diagram to show how a ray of light is refracted when it passes : (a) from air into an optically denser medium. (b) from an optically denser medium into air.

Q. A combination of two prism of, one of flint glass and the other of crown glass produces dispersion without deviation. The angle of flint glass prism is 15^° . Calculate dispersion of red and violet light. (Ref index of crown glass=1.52 and flint glass=1.65) ( for crown glass=0.02 and for flint glass=0.03)

Q.

Draw a labelled ray diagram to show how a ray of light passes through a parallel sided glass block : (a) if it hits the glass block at 90° (that is, perpendicular to the glass block) (b) if it hits the glass block at an angle other than 90° (that is, obliquely to the glass block).

Q.

A water pond appears to be $2.5\mathrm{m}$ deep. If the refractive index of water is $\frac{4}{3}$. Determine the actual depth of the pond.

Q.

Refractive index of glass is $\frac{3}{2}$. A ray of light travelling in glass is incident on glass-water surface at an angle 30° with normal. Will it be able to come out into the water. Refractive index of water = $\frac{4}{3}$.

Q.

A plane mirror is approaching you at 10 cm $s^{-1}$. Your image shall approach you with a speed of __.

Q. Draw a labelled ray diagram of refraction of light through a parallel glass slab and triangular glass prism.

Q. Explain the refraction of light through a glass-slab with neat ray diagram.

Q.

Two isosceles right-angled glass prisms are placed near each other as shown in the following figure:

The path of the light ray entering the first isosceles right-angled glass prism till it emerges from the second identical prism is such that

1. The light emerges parallel to the incident ray from the second prism

2. The light takes a 90^o turn

3. The light emerges perpendicular to the incident ray from the second prism

4. The light takes a 180^o turn

Q. "During refraction of light through the glass slab, incident ray and emergent ray are parallel to each other." Explain.

Q.

A ray of light passes from glass into air, angle of refraction; (a) equal to the angle of incidence (b) greater than the angle of incidence (c) smaller than the angle of incidence (d) ${45}^{\circ }$

Q.

Why does the pencil appear bent when dipped partially in a beaker containing water?

Q. What is refraction of light? Draw the diagram of refraction of light in glass slab. Write the laws of refraction.

Q. Lateral displacement through a glass slab does not depend on

1. Thickness of the slab
2. Angle of incidence
3. Angle of refraction
4. Frequency of light

Q.

What path does a ray of light travel when it suffers minimum deviation while passing through an equilateral prism?

1. The emergent ray travels parallel to the incident ray

2. The emergent ray travels parallel to the refracted ray

3. The refracted ray travels parallel to the base of the prism

4. The emergent ray travels parallel to the base of the prism

5. The emergent ray travels perpendicular to the base of the prism

Q. After refraction of light through a glass slab, incident ray and emergent ray are:

1. Perpendicular
2. Parallel
3. In a straight line
4. None of these

Q. In the given figure, when light emerges from the glass slab, the light ray bends ___ .

1. towards the normal
2. away from the normal
3. parallel to the normal
4. away from the emergent ray

Q. A ray of light enters into a glass slab of refractive index μ from air. If λ is wavelength of light in air, then the wavelength of light in glass slab is

1. $\frac{\lambda }{\mu }$
2. λ
3. μλ
4. $\frac{\mu }{\lambda }$