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प्रश्न
What is a rainbow? What are the two conditions necessary for the formation of a rainbow in the sky?
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उत्तर
A rainbow is a natural spectrum of seven colours formed in the sky when the water droplets in the atmosphere cause the dispersion of sunlight. The two conditions necessary for the formation of a rainbow are as follows.
1. The sun should be shining.
2. It should be raining.
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संबंधित प्रश्न
A student traces the path of a ray of light through a triangular glass prism for different values of angle of incidence. On analyzing the ray diagrams, which one of the following conclusions is he likely to draw?
(A) The emergent ray is parallel to the incident ray.
(B) The emergent ray bends at an angle to the direction of the incident ray.
(C) The emergent ray and the refracted ray are at right angles to each other.
(D) The emergent ray is perpendicular to the incident ray.
Study the following figure in which a student has marked the angle of incidence (∠i), angle of refraction (∠r), angle of emergence (∠e), angle of prism (∠A) and the angle of deviation (∠D). The correctly marked angles are
(a) ∠A and ∠i
(b) ∠A, ∠i and ∠r
(c) ∠A, ∠i, ∠e and ∠D
(d) ∠A, ∠i, ∠r and ∠D
What happens when a ray of ordinary light is passed through a triangular glass prism?
What will happen if another similar glass prism is placed upside down behind the first prism?
What is spectrum? What is the name of glass shape used to produce a spectrum?
In the figure given alongside, a narrow beam of white light is shown to pass through a triangular glass prism. After passing through the prism, it produces a spectrum YX on the screen.
State the colour seen (i) at X, and (ii) at Y.
Name the process which is involved in the formation of a rainbow.
Out of the following, the colour of light having the maximum wavelength is:
(a) violet
(b) indigo
(c) green
(d) orange
The splitting of white light into its constituent colours is called .............
You are given a disc divided into seven sectors with colours violet, indigo, blue, green, yellow, orange and red in them. What would be its colour when it is rotated rapidly?
- A beam of monochromatic light undergoes minimum deviation through an equiangular prism, how does the beam pass through the prism, with respect to its base?
- If white light is used in the same way as in part (a) above, what change do you expect in the emergent beam?
- What conclusion do you draw about the nature of white light in part (b)?
Refer to fig
(i) Name the lens L.
(ii) What are the points O, O' called?
(iii) Complete the diagram to form the image of the object AB.
(iv) Write three characteristics of the image.
An object AB is placed in front of a convex lens as shown in fig. 4. Complete the ray diagram and obtain the image formed and state the nature of the image.
An object is placed in front of a converging lens and in front of a diverging lens as in fig.
(a)Complete the ray diagram to obtain an image.
(b)Compare the nature of image formed by both the lenses in the above case.
A wave has wavelength 50Å of name the wave.
Draw a labelled diagram: Dispersion of light through a prism.
How can the presence of ultraviolet radiation be detected?
Write an Explanation.
Critical angle
Name the scientist who was the first to use a glass prism to obtain the spectrum of sunlight.
Which one of the following is involved for the formation of rainbow in the sky?
