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प्रश्न
What is a spectrum?
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उत्तर
The band of colored components of a beam of light is called a spectrum.
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संबंधित प्रश्न
After tracing the path of a ray of light passing through a rectangular glass slab for four different values of the angle of incidence, a student reported his observations in tabular form as given below:
| S.No | ∠ i | ∠ r | ∠ e |
| I | 30° | 19° | 29° |
| II | 40° | 28° | 40° |
| III | 50° | 36° | 50° |
| IV | 60° | 40° | 59° |
The best observation is
(A) I
(B) II
(C) III
(D) IV
Draw a ray diagram to show the refraction of light through a glass slab and mark angle of refraction and the lateral shift suffered by the ray of light while passing through the slab.
Four students P, Q, R and S traced the path of a ray of light passing through a glass slab for an angle of incidence 40° and measured the angle of refraction. The values as measured them were 18°; 22°; 25° and 30° respectively. The student who has performed the experiment methodically is
(A) P
(B) Q
(C) R
(D) S
Explain the term absolute refractive index of a medium and write an expression to relate it with the speed of light in vacuum.
Name one factor that affects the lateral displacement of light as it passes through a rectangular glass slab.
Draw the diagram of refraction of light in the glass slab
Observe the following figure and answer the questions given under it:
1) How many times does refraction take place in the above figure?
2) What happens to the ray of light when it passes from air to glass?
3) What happens to the ray of light when it passes from glass to air?
4) What are the rays AB and CD in the figure called?
5) Define refraction.
In the adjacent diagram, AO is a ray of light incident on a rectangular glass slab.
- Complete the path of the ray till it emerges out of the slab.
- 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?
- Mark angles of emergence by the letter e. How are the angles i and e related?
- Which two rays are parallel to each other? Name them.
- Indicate in the diagram the lateral displacement between the emergent ray and the incident ray. State one factor that affects the lateral displacement.
A ray of light of wavelength 6600 Å suffer refraction from air to glass. Taking \[\ce{_a\mu_g = \frac{3}{2}}\], find the wavelength of light in glass.
How does the speed of light change when it passes from glass to water?
Fig 4.31 below shows a light ray of single colour incident normally on two prisms A and B. In each case draw the path of the ray of light as it enters and emerges out of the prism. Mark the angle wherever necessary.
The refractive index of glass is 1.5. From a point P inside a glass block, draw rays PA, PB and PC incident on the glass air surface at an angle of incidence 30°, 42° and 60° respectively.
- In the diagram show the approximate direction of these rays as they emerge out of the block.
- What is the angle of refraction for the ray PB?
`("Take" sin 42° =2/3)`
Observe the figure and write accurate conclusion regarding refraction of light.
In the fig. name the ray which represents the correct path of light while passing through a glass block.
Fill in the blank to complete the following sentence:
When light travels from a rarer to a denser medium, it bends ...........
Fig shows a lens as a combination of a glass block and two prisms.
(i) Name the lens formed by the combination.
(ii) what is the XX' called?
(iii) Complete the ray diagram and show the path of the incident ray PQ after passing through the lens.
(iv) The final emergent ray will either meet XX' at a point or appear to come from a point on XX'. what is the point called?
Draw a diagram to show the splitting of white light into its constituent colours.
Fig. shows a ray of white light that passes through a prism and produces a spectrum.
(a) Name the phenomenon that is taking place.
(b) What colour would you see at X and Y?
(c) What radiation would you detect above X and below Y?
Light of a single colour is passed through a liquid having a piece of glass suspended in it. On changing the temperature of liquid, at a particular temperature, the glass piece is not seen.
Why is the light of a single colour used ?
A total reflecting equilateral prism can be used to deviate a ray of light through:
Glass is transparent in nature. Why does glass powder look opaque? When water is poured over it, it again becomes transparent. Why?
Why is the colour red used as a sign of danger?
Write a relation between the angle of incidence (i), angle of emergence (e), angle of the prism (A), and angle of deviation (d) for a ray of light passing through an equilateral prism.
State the factors on which the angle of deviation depends.
What is the refractive index of water
State the relation between the refractive index μ and the velocity of light (vm) in that medium.
How is the refractive index of a medium related to its real depth and apparent depth?
Express the refractive index μ of a medium in terms of the velocity of light.
In what condition a prism is said to be in the position of minimum deviation? What is the direction of the refracted ray inside the prism in this condition?
You are provided with a printed piece of paper. Using this paper how will you differentiate between a convex lens and a concave lens?
Light passes through a rectangular glass slab and through a triangular glass prism. In what way does the direction of the two emergent beams differ and why?
A ray of light PQ is incident normally on the hypotenuse of a right-angled prism ABC as shown in the diagram given below:
(i) Copy the diagram and complete the path of the ray PQ till it emerges from the prism.
(ii) What is the value of the angle of deviation of the ray?
(iii) Name an instrument where this action of the prism is used.
The refractive index of glass with respect to air is 3/2. What is the refractive index of air with respect to glass?
