Advertisements
Advertisements
प्रश्न
Solve Numerical example.
From the given data set, determine angular dispersion by the prism and dispersive power of its material for extreme colours. nR = 1.62 nV = 1.66, δR = 3.1°
Advertisements
उत्तर
Given: nR = 1.62, nV = 1.66, δR = 3.1°
To find: i. Angular dispersion (δVR)
ii. Dispersive power (ωVR)
Formula: i. δ = A (n − 1)
ii. δVR = δV − δR
iii. ω = `(δ_"V"-δ_"R")/(((δ_"V"+δ_"R")/2))`
Calculation: From formula (i),
δR = A(nR − 1)
∴ A = `δ_"R"/(("n"_"R"-1))=3.1/((1.62-1))=3.1/0.62`
∴ δV = A(nV − 1) = 5 × (1.66 − 1) = 3.3°
From formula (ii),
δVR = 3.3 − 3.1 = 0.2°
From formula (iii),
ωVR = `(3.3-3.1)/(((3.3+3.1)/2))=0.2/6.4xx2=0.2/3.2=1/16`
= 0.0625
- Angular dispersion by prism is 0.2°
- Dispersive power of material of prism is 0.0625.
APPEARS IN
संबंधित प्रश्न
The figure shows a ray of light falling normally on the face AB of an equilateral glass prism having refractive index`3/2`, placed in water of refractive index `4/3`.Will this ray suffer total internal reflection on striking the face AC? Justify your answer.

State the relation between the critical angle and the absolute refractive index of a medium.
Draw the diagram of a right-angled isosceles prism which is used to make an invented image erect.
State two conditions necessary for total internal reflection to occur.
Write the relation between the refractive index and critical angle for a given pair of optical media?
If a light ray does not undergo, refraction at the boundary between two media, the angle of incidence is:
(a) A ray of monochromatic light enters glass PQRS as shown in the fig. Complete the path of ray till it emerges from the glass. (Critical angle of glass is 420).

(b) Draw diagram of a prism periscope.
(c) What are the advantages of total internal reflecting prism over plane mirror?
Name the principle on the basis of which optical fibres work.
How does a ray of light bend when it travels from when it is normal to the interface of the two media.
Express the refractive index μ of a medium in terms of the angle of incidence i in air and the angle of refraction r in a denser medium.
If a ray of light passes from medium I to medium II without any change of direction, what can be said about the refractive indices of these media (angle I is not 0)?
A ray of light incident at an angle of incidence ‘i’ passes through an equilateral glass prism such that the refracted ray inside the prism is parallel to its base and emerges from the prism at an angle of emergence ‘e’.
How is the angle of emergence ‘e’ related to the angle of incidence ‘i’?
Choose the correct option.
Select the WRONG statement.
Choose the correct option.
Angles of deviation for extreme colours are given for different prisms. Select the one having maximum dispersive power of its material.
Answer the following question.
Define the critical angle of incidence and obtain an expression for it.
Answer the following question.
What are the advantages of optical fibre communication over electronic communication?
Observe the given figure and write appropriate phenomenon of light in the box.

Which one of the following is NOT the correct formula for refractive index of glass w.r.t. air (aμg) (i = angle of incidence, r = angle of refraction)
Optical fibre communication uses the principle of ______.
A bundle of glass threads, each of which is capable of transmitting messages using light waves is called ______.
Optical Fibres are based on the phenomenon of dispersion.
What is a mirage? How does it occur?
What are the examples of total internal reflection in nature?
State the condition under which total internal reflection occurs. Give the mathematical expression for total internal reflection.
A Rainbow is a beautiful natural phenomenon formed because of the following:
Observe the given figure of the raindrop and answer the following questions:

- Label A and B of the given diagram. Why colour will deviate most.
- Name the phenomenon shown in label C.
A given ray of light suffers minimum deviation in an equilateral prism P. Additional prism Q and R of identical shape and of the same material as P are now added as shown in the figure. The ray will now suffer ______.

Small air bubbles rising up a fish tank appear silvery when viewed from some particular angle is due to the ______.
