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प्रश्न
What are the seven colours seen in a rainbow?
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उत्तर
The seven colours seen in a rainbow are red, orange, yellow, green, blue, indigo and violet.
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संबंधित प्रश्न
The path of a ray of light passing through a glass prism is shown below:
In this diagram, the angle of prism, angle of incidence, angle of emergence and angle of deviation, respectively, have been represented by:
(A) O, Y, Z and N,
(B) P, Y, M and Z,
(C) O, X, M and Z,
(D) P, X, Z and N.
A student is observing a diagram showing the path of a ray of light passing through a glass prism. He would find that for all angles of incidence the ray of light bends:
Fill in the blank with suitable word:
When a ray of light enters a prism, it bends ................ the normal ; as it leaves the prism, it bends ................. the normal.
Which of the following colour of white light is least deviated by the prism?
(a) green
(b) violet
(c) indigo
(d) yellow
The splitting of white light into its constituent colours is called .............
Explain briefly, with the help of a neat labelled diagram, how white light gets dispersed by a prism. On which surface of a prism, there is both dispersion and deviation of light, and on which surface of the prism, there is only deviation of light ?
A ray of white light is passed through a glass prism and a spectrum is obtained on a screen.
- Name the seven colours of the spectrum in order.
- Do the colours have the same width in the spectrum?
- Which of the colour of the spectrum of white light deviates (i) the most, (ii) the least?
In an experiment to trace the path of a ray of light through a triangular glass prism, a student would observe that the emergent ray
(a) is parallel to the incident ray.
(b) is along the same direction of incident ray.
(c) gets deviated and bends towards the thinner part of the prism.
(d) gets deviated and bends towards the thicker part (base) of the prism.
A glass prism is able to produce the spectrum when white light passes through it, but a glass slab doesn’t produce any spectrum. Explain why it is so.
If a monochromatic beam of light undergoes minimum deviation through an equiangular prism, how does the beam pass through the prism, with respect to its base?
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.
Write three conditions necessary to obtain a pure spectrum on a screen. Name the instrument in which the conditions stated by you are fulfilled.
What do you understand by spectrum? Name the seven prominent colours in order, as obtained in the spectrum of white light.
Distinguish between an impure spectrum and a pure spectrum.
Write the range of wavelength of the visible spectrum.
Suggest one way, in each case, by which we can detect the presence of Infrared radiations.
The process of separation of light into its component colours while passing through a medium is called _______.
Rainbow is a beautiful natural phenomenon. It is the combined effect of a natural three processes together produced by light. Write it into the circle.
______ colour is deviated the least in the spectrum of white light obtained with a glass prism.
The dispersive powers of flint glass and crown glass are 0.053 and 0.034, respectively and their mean refractive indices are 1.68 and 1.53 for white light. Calculate the angle of the flint glass prism required to form an achromatic combination with a crown glass prism of refracting angle 4°:
