Minimum Deviation

Q.

A ray of light is normally incident on one face of an equilateral glass prism. Answer the following:

(a) What is the angle of incidence on the first face of the prism?

(b) What is the angle of refraction from the first face of the prism?

(c) What will be the angle of incidence at the second face of the prism?

(d) Will the light ray suffer minimum deviation by the prism?

Q.

Define angle of prism

Q.

The value of angle of deviation produced by a prism varies with an increase in the value of angle of incidence as follows:

1. As the angle of incidence increases, first the angle of deviation increases then for a certain angle of incidence, the angle of deviation becomes minimum and then the angle of deviation decreases.

2. As the angle of incidence increases, first the angle of deviation decreases then for a certain angle of incidence, the angle of deviation becomes minimum and then the angle of deviation increases.

3. As the angle of incidence increases, first the angle of deviation decreases then for a certain angle of incidence, the angle of deviation becomes maximum and then the angle of deviation increases.

4. As the angle of incidence increases, first the angle of deviation increases then for a certain angle of incidence, the angle of deviation becomes maximum and then the angle of deviation decreases.

Q. In a prism, is angle of incidence always equal to angle of emergence?

Q. ntA light ray of angle of incidence 40 degree emerged from the prism in minimum deviation position. Then what is the angle of incidence on the second surface?n

Q.

What happens when a narrow beam of (i) monochromatic light and (ii) white light passes through (a) glass slab and (b) glass prism

Q.

The angle between incident ray and emergent ray of prism is called

1. angle of incidence

2. angle of refraction

3. angle of deviation

4. angle of emergence

Q.

Explain the dispersion of light through a prism

Q.

Angle of deviation depends upon which of the following

1. angle of prism

2. nature of material of the prism

3. All of the above

4. angle of incidence

Q.

A light ray falls on one of the faces of a prism at an angle 40 so that it suffers minimum deviation of 30 degrees. Find the angle of prism and angle of refraction at the given surface.

Q.

The given diagram shows a ray of light incident on an equilateral glass prism placed in minimum deviation position. How are angle of incidence and angle of emergence related to each other in this position of the prism?

1. Angle of incidence (i) + Angle of emergence (e) = 90^o

2. Angle of incidence (i) < Angle of emergence (e)

3. Angle of incidence (i) = Angle of emergence (e)

4. Angle of incidence (i) > Angle of emergence (e)

Q.

In the given figure, a ray of light PQ is incident normally on one face AB of an equilateral glass prism. The angles of incidence at the faces AB and AC are:

1. 90^o and 60^o

2. 0^o and 60^o

3. 60^o and 0^o

4. 0^o and 30^o

Q. What is deviation of light

Q. Why the angle of deviation in prisms first decreases and then increases and besides this why the angle of deviation increases with the increase of angle of prism

Q.

An equilateral prism is placed on a horizontal surface. A ray PQ is incident onto it. For minimum deviation:

1. QR is horizontal

2. PQ is horizontal

3. RS is horizontal

4. Any one will be horizontal

Q.

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 prism?

Q. A ray of light incident at an angle of 37° on a prism of refracting angle 60° suffers minimum deviation. The angle of minimum deviation is

Q. A ray of light incident at an angle ${48}^o$ on a prism refracting angle ${60}^o$ suffers minimum deviation. Calculate the angle of minimum deviation.

1. ${72}^o$
2. ${18}^o$
3. ${36}^o$
4. ${54}^o$

Q.

Draw a ray diagram to show the refraction of a monochromatic ray through a prism when it suffers minium deviation. How is the angle of emergence related to the angle of incidence in this position?

Q. One of the conditions given for minimum angle of deviation in glass prism is that the refracted ray becomes parallel to the base. So, if in any case the refracted ray is parallel to the base does it imply that it is case for minimum deviation and i = e

Q. For a prism, angle of prism is ${60}^{\circ }$ and its refractive index is $1.5$. Find angle of incidence corresponding to the angle of minimum deviation.

Q. While doing the experiment to trace the path of light ray through a triangular glass prism, the, students are advised to take angle of incidence not less than 30 degree, because : (a) it becomes difficult to locate the position of object (pins). (b) three images of object are formed. (c) blurred image of object is formed. (d) image of object is not formed.

Q. In an equilateral prism if the angle of incidence for minimum angle of deviation is ${35}^0$ then what is the minimum angle of deviation?

1. ${30}^0$
2. ${20}^0$
3. ${10}^0$
4. ${45}^0$

Q. A ray of light suffers minimum deviation, while passing through a prism of refractive index 1.5 and refracting angle 60${}^o$. Calculate the angle of deviation and angle of incidence.

Q. A parallel beam of monochromatic light is incident at one surface of a equilateral prism. Angle of incidence is ${55}^o$ and angle of emergence is ${46}^o$. The angle of minimum deviation will be

1. None of the above
2. Less than ${41}^o$
3. More than ${41}^o$
4. Equal to ${41}^o$

Q. Two prisms A and B are in contact with each other have angular dispersion of $2^o$ and $4^o$ respectively The dispersive power of 'A' is 0.002. If the combination produces dispersion without deviation that dispersive power of 'B'

1. $0.002$
2. $0.006$
3. $0.001$
4. $0.004$

Q. 1. A ray of light incident at an angle of incidence 48° on a prism of refracting angle 60° suffers minimum deviation. Calculate the angle of minimum deviation.
[Hint : δ_min = 2i – A]

2. What should be the angle of incidence for a ray of light which suffers minimum deviation of 36° through an equilateral prism?
[Hint : A = 60°, i = (A + δ_min) / 2]

Q. A ray of light is incident normally on one face of an equilateral prism of refractive index $1.5$.
The angle of deviation is:

1. ${75}^o$
2. ${30}^o$
3. ${45}^o$
4. ${60}^o$

Q. A prism of refractive index 1.53 is placed in water of refractive index 1.33. If the angle of the prism is 60${}^o$, calculate the angle of minimum deviation in water.

Q.

The figure shows an equilateral prism ABC and the ray QR emerging out from the prism after suffering minimum deviation. Complete the diagram to show the refracted ray PQ inside the prism and the incident ray OP on the prism. State in words how have you completed the diagram. ​