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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
Explain how spectrum is formed.
When rays of light are incident on a glass slab then the incident ray and emergent ray are _________ each other.
- perpendicular
- parallel
- opposite
- concurrent
Choose the correct alternative and rewrite the following sentence.
A ray of light strikes the glass slab at an angle of 50°. What is the angle of incidence?
Explain how the formation of a rainbow occurs.
A student traces the path of a ray of light through a rectangular glass slab for the different values of angle of incidence. He observes all possible precautions at each step of the experiment. At the end of the experiment, on analyzing the measurements, which of the following conclusions is he likely to draw?
(A) ∠i = ∠e < ∠r
(B) ∠i < ∠e < ∠r
(C) ∠i > ∠e > ∠r
(D) ∠i = ∠e > ∠r
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.
Why do we get a spectrum of seven colors when white light is dispersed by a prism?
The speed of light in glass is 2 × 105 km/s. What is the refractive index of glass?
Name a prism required for obtaining a spectrum of Ultraviolet light.
Why is the ratio of the velocities of light of wavelengths 4000Å and 8000Å in vacuum 1: 1?
The following diagram shows a 60°, 30°, 90° glass prism of critical angle 42°, Copy the diagram and complete the path of incident ray AB emerging out of the prism marking the angle of incidence on each surface.
For which colour of white light, is the refractive index of a transparent medium the most?
A ray of light strikes the surface of a rectangular glass block such that the angle of incidence in
air is 0°.
In each case, draw diagram to show the path taken by the ray as it passes through the glass block and emerges from it.
When a ray of light from air enters a denser medium, it ______.
In fig 4.18, name the ray which represents the correct path of light while emerging out through a glass block.
The refractive index of air with respect to glass is expressed as `""_g μ_a=sin i /sin r`.
- Write down a similar expression for aμg in terms of the angles i and r.
- If angle r = 90°, what is the corresponding angle i called?
- What is the physical significance of the angle i in part (b)?
A ray of light enters a glass slab ABDC as shown in figure and strikes at the centre O of the circular part AC of the slab. The critical angle of glass is 42°. Complete the path of the ray till it emerges out from the slab. Mark the angles in the diagram wherever necessary.
Four students showed the following traces of the path of a ray of light passing through a rectangular glass slab.
The trace most likely to be correct is that of student
(A) I
(B) II
(C) III
(D) IV
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?
Using the curve, how do you infer that for given prism, the angle of minimum deviation δmin is unique for the given light?
A total reflecting equilateral prism can be used to deviate a ray of light through:
Choose the correct alternative and rewrite the following:
A glass slab is placed in the path of convergent light. The point of convergence of light
Name the phenomenon responsible in the following case:
Twinkling of stars
Name one main factor on which the direction of bending of a ray of light depends.
During sunset and sunrise, the sun is seen when it is slightly below the horizon. Give reason.
What is the refractive index of water
How is the refractive index of a medium related to its real depth and apparent depth?
What is the total reflecting prism?
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?
Draw ray of light bending towards the normal while passing from glass to water. Label your diagrams.
The figure shows two prisms A and B. A monochromatic ray of light PO is incident at the face of the prism A. Complete the diagram to show the path of the ray till it emerges out of the prism B.
How will you verify the laws of refraction or how the refractive index of glass is determined in the laboratory?
Trace a ray of light incident at 30° on a surface if travelling from air to glass. What is the angle of refraction in this case? (R.I. for glass = 3/2).
Trace a ray of light incident at 30° on a surface if travelling from glass to air. What is the angle of refraction in this case? (R.I. for glass = 3/2).
The speed of light in air is 3 × 108 ms-1. Calculate the speed of light in water. The refractive index of water is 4/3.
