Angle of Deviation

Q. The angle of a prism is ${60}^{\circ }$ and its refractive index is $\sqrt{2}$. The angle of minimum deviation suffered by a ray of light in passing through it is:

1. About 20°
2. 30°
3. 60°
4. 45°

Q.

Why can't a glass slab disperse light?

Q. A prism with an angle A=60° produces an angle of minimum deviation 30°.Then the refractive index of the material of prism

Q. Why dispersion of white light takes place only in a prism and not in glass slab?

Q. State giving reason how the speed of red light is compared with the speed of blue light in vacuum and in glass.

Q.

The angle of dispersion depends on?

Q.

A ray of light falls on one face of an equilateral glass prism at ${40}^{\circ }$ and emerges from the other face at the same angle. The deviation suffered by the ray is

1. ${40}^{\circ }$

2. ${60}^{\circ }$

3. ${80}^{\circ }$

4. ${20}^{\circ }$

Q.

What do you understand by the deviation produced by a prism? Why is it caused? State three factors on which the angle of deviation depends.

Q.

How does the deviation produced by a prism depend on (i) the frefractive index of its material, and (ii) the wavelength of incident light.

Q.

An object in a denser medium, when viewed from a rarer medium, appears to be raised. The shift is maximum for:

(a) red light (b) violet light

(c) yellow light (d) green light

Q.

Prism angle and refractive index for a prism are ${60}^{\circ }$ and $1.414$ respectively. Then what will be the Angle of minimum deviation?

1. ${30}^{\circ }$

2. ${45}^{\circ }$

3. ${60}^{\circ }$

4. ${15}^{\circ }$

Q. What will happen if we keep a glass prism inside water instead of air and pass white light through it?

1. The angle of deviation of each splitted ray will increase.
2. White light will pass it without splitting.
3. The angle deviation of each splitted ray will decrease.
4. Splitted red light will bend more than the splitted blue light.

Q.

Explain briefly, with the help of a neat labelled diagram, how does white light gets dispersed by a prism. On which surface of the prism, there is both the dispersion and deviation of light?

Q. State 5 differences between refraction by glass prism and glass slab. (Note:In TABULAR form)

Q.

(a) For which colour of white light, is the refractive index of a transparent medium (i) the least, (ii) the most?

(b) Which colour of light travels fastest in any medium except air?

Q.

Compare refraction in glass slab and in glass prism .

Q.

As light rays travel from air into a glass prism, they deviate

1. cannot be determined

2. do not deviate.

3. away from the normal.

4. towards the normal.

Q.

A prism is said to be in minimum deviation when

Q. Through a prism, red light deviates more than blue light.

1. True
2. False

Q. In a prism, why does the angle of deviation increase as the angle of prism increases?

Q.

A ray of light falls on one face of an equilateral glass prism at ${40}^{\circ }$ and emerges from the other face at the same angle. The deviation suffered by the ray is

1. ${20}^{\circ }$

2. ${40}^{\circ }$

3. ${60}^{\circ }$

4. ${80}^{\circ }$

Q. What is the cause of dispersion.and why dispersion is not shown rectangular glass slab

Q. In a thin prism of glass (refractive index $1.5$), which of the following relations between the angle of minimum deviation ${\delta }_m$ and angle of refraction $r$ will be correct?

1. ${\delta }_m=r$
2. ${\delta }_m=1.5r$
3. ${\delta }_m=2r$
4. ${\delta }_m=\frac{r}{2}$

Q. A prism has a refracting angle of 60${}^{\circ }$. When placed in the position of minimum deviation, it produces a deviation of 30${}^{\circ }$. The angle of incidence is:

1. 45${}^{\circ }$
2. 30${}^{\circ }$
3. 15${}^{\circ }$
4. 60${}^{\circ }$

Q. Refractive index of a medium _______ with increases in wavelength of light.

1. increases
2. decreases
3. remains same
4. cant say

Q. Alex is doing an experiment with a white laser light inside a dark lab.
(ii) How will he use two identical prisms so that a narrow beam of white light incident on one prism emerges out of the second prism as white light? Draw the diagram.

Q.

A ray of light is normally incident on one face of an equilateral glass prism. What is the angle of incidence on the first face of the prism?

A. $0^{\circ }$
B. ${30}^{\circ }$
C. ${45}^{\circ }$
D. ${90}^{\circ }$

Q. Find angle minimum deviation of an equilateral prism $(\mu =1.732)$. Also find angle of incidence for this deviation.

1. ${60}^{\circ },{75}^{\circ }$
2. ${60}^{\circ },{55}^{\circ }$
3. ${60}^{\circ },{50}^{\circ }$
4. ${60}^{\circ },{60}^{\circ }$

Q. In the following diagram, the path of a ray of light passing through a glass prism is shown :
In this diagram the angle of incidence, the angle of emergence and the angle of deviation respectively are (select the correct option) :

1. Y, Q and T
2. X, Q and P
3. Y , Q and P
4. X, R and T

Q. (a) How does the deviation produced by a prism depend on
(i) the refraction index of its material, and
(ii) the wavelength of incident light

(b) How does the angle of minimum deviation produced by a prism change with increase in (i) the wavelength of incident light and (ii) the refracting angle of the prism?