Minimum Deviation

Q. An equilateral prism has angle of minimum deviation 30^° .Find total deviation if a ray is incident normally on a surface

Q. When a glass prism of refracting angle ${60}^{\circ }$ is immersed in a liquid, its angle of minimum deviation is ${30}^{\circ }$. The critical angle of glass with respect to the liquid medium is

1. ${30}^{\circ }$
2. ${45}^{\circ }$
3. ${50}^{\circ }$
4. ${60}^{\circ }$

Q. An equilateral prism has angle of minimum deviation ${30}^{\circ }$ when the angle of incidence is ${60}^{\circ }$. The angle of deviation of emergent ray is $10n$ degrees if the ray is incident normally on a surface. n is (Write upto two digits after the decimal point.)

Q.

A ray of light is incident at an angle of incidence ‘i’ on one face of a prism of angle A (assumed to be small) and emerge normally from the opposite face. If the refractive index of the prism is $\mu ,$ the angle of incidence i, is nearly equal to:

1. $\mu A$
2. $\frac{\mu A}{2}$
3. $\frac{A}{\mu }$
4. $\frac{A}{2\mu }$

Q.

A beam of monochromatic light is incident at i=50° on one face of an equilateral prism, the angle of emergence is 40°, then the angle of minimum deviation is :

(A) 30° (B) <30° (C) ≤30° (D)≥30°

Q.

What are the necessary conditions which are to be followed to obtain a pure spectrum on a screen?

Q. A prism having an apex angle $4^{\circ }$ and refractive index 1.5 is located in front of a vertical plane mirror as shown in figure. Through what total angle is the ray deviated after reflection from the mirror

1. $2^{\circ }$
2. ${176}^{\circ }$
3. $4^{\circ }$
4. ${178}^{\circ }$

Q. The angle of incidence for an equilateral prism is ${60}^{\circ }$. What should be the refractive index of prism so that the ray is parallel to the base inside the prism?

1. $\sqrt{2}$
2. $\sqrt{3}$
3. $\frac{4}{3}$
4. $\frac{9}{8}$

Q. If the angle of prism is 60^° and angle of minimum deviation is 40^°, the angle of refraction of first refracting surface of prism will be

Q. Angle of glass prism is ${60}^{\circ }$ and refractive index of the material of the prism is 1.414, then what will be the angle of incidence, so that ray should pass symmetrically through prism

1. ${53}^{\circ }{8}^{\prime }$
2. ${38}^{\circ }{61}^{\prime }$
3. ${35}^{\circ }{35}^{\prime }$
4. ${45}^{\circ }$

Q. 52.At what angle will a Ray of light incident on one face of an equilateral prism so that the emergent ray grazes the second surface of the prism(u=2) 1) 30 degree 2) 90 degree 3) 45 degree 4) 60 degree

Q.

Find the angle of deviation suffered by the light ray shown in figure. The refractive index $\mu =1.5$ for the prism material.

Q.

The refractive index of the material of a prism is $1.5$ and the angle of the prism is $6°$. find the deviation produced by the prism for a small angle of incidence.

Q. The angle of minimum deviation for prism angle $\frac{\pi }{3}$ is $\frac{\pi }{6}$. Calculate the velocity in the material of the prism, if the velocity of light in vacuum is $3.00\times {10}^{8}m{s}^{-1}$.

1. $2.12\times {10}^{8}m{s}^{-1}$
2. $3.00\times {10}^{8}m{s}^{-1}$
3. $3.50\times {10}^{8}m{s}^{-1}$
4. $2.50\times {10}^{8}m{s}^{-1}$

Q.

A prism of refractive index and refractive angle A produces minimum deviation δ_m of a ray on one face at an angle of incidence 45⁰. The values of A and δ_m are respectively

1. 60⁰, 30⁰

2. 45⁰, 60⁰

3. 45⁰, 45⁰

4. 60⁰, 45⁰

Q. Find the angle of deviation in the given figure.

1. ${15}^{\circ }$ anticlockwise
2. ${15}^{\circ }$ clockwise
3. ${30}^{\circ }$ clockwise
4. ${37}^{\circ }$ clockwise

Q. 35.A light ray of angle of incidence 40degree emerged from the prism in minimum deviation position. Then what is the angle of incidence on second surface? (1)90 (2)0 (3)40 (4)20

Q. In the case of dispersion without deviation why is the net dispersion=theta 1 + theta 2?My logic is that as the two prisms are kept in the opposite sense they are dispersing it in the opposite direction i.e. when the white light goes through the first prism the violet light is deviated the most towards the base of the prism then when the light enters the second prism the violet light is deviated upwards(which is in the opposite sense) this the angular dispersion is in the opposite sense in first and the second prism and the net dispersion should be =theta 1-theta 2

Q. . Find the angle of deviation if angle of incidence is 35 degree

Q. A parallel beam of light is incident on a face of a prism of refracting angle 60^° . Find the refractive index of the prism if the angle of minimum deviation is 40^° . What is the new angle ofminimum deviation if the prism is immersed in water of refractive index 1.33?

Q. A ray of light incident on a ${60}^{\circ }$ angled prism of refractive index $\sqrt{2}$ suffers minimum deviation. Angle of incidence is

1. ${70}^{\circ }$
2. $0^{\circ }$
3. ${45}^{\circ }$
4. ${30}^{\circ }$

Q. 35.Define dispersive power of a prism.Calculate the dispersive power for a prism for following data

Q. 13.The following table gives the values of the angle of deviation for different values of the angle of incidence for a triangular prism Angle of incidence:33*, 38*, 42*, 52*, 60*, 71* Angle of deviation:60*, 50*, 46*, 40*, 43*, 50*, For what values of the angle of incidence , is the angle of emergence likely to be equal to the angle of incidence itself?

Q.

A ray of light strikes a glass plate at an angle of $60°$. If the reflected and refracted rays are perpendicular to each other, then the refractive index of glass is

Q. Dispersive power of a prism decreases with the increase in prism angle.

1. True
2. False

Q. A prism is made of glass of unknown refractive index. A parallelbeam of light is incident on a face of the prism. The angle of minimumdeviation is measured to be 40°. What is the refractive index of thematerial of the prism? The refracting angle of the prism is 60°. Ifthe prism is placed in water (refractive index 1.33), predict the newangle of minimum deviation of a parallel beam of light.

Q. A ray is incident on a prism of $\mu =\sqrt{2}$. Find the length of the optical path covered by ray inside the prism.

1. $\sqrt{\frac{400}{3}}$
2. $\sqrt{\frac{512}{3}}$
3. $\sqrt{\frac{256}{3}}$
4. $\sqrt{\frac{441}{3}}$

Q. 68.The angle of incidence for a ray of light at a retracting surface of a prism is 45 degree.the angle of prism is 60 degree.if the ray suffers minimum deviation through the prism the angle of minimum deviation and refractive index of the material of the prism is?

Q. A light is incident at 74 degree on an equilateral prism and deviation angle of 55 is obtained. How much the angle ofincidence should be reduced so that same derivation angle is obtaine (1)33degree (2) 27degree (3)19degree (4)51de

Q.

A beam of unpolarized light is incident on an air-glass interface derive, using a suitable ray diagram that light reflected from the interface is completely polarised, when $\tan i_p=?$