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प्रश्न
Why do you not see a spectrum of colours when light passes through a flat pane of glass?
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उत्तर
When light passes through a flat pane of glass, the refracted light emerges out of the glass pane without any deviation because a glass pane has two sides that are parallel to each other. As the emergent light does not deviate from the original direction by any angle, we do not see the different colours of the light separated out in the form of a spectrum. Therefore, in order to view a spectrum of colours, the incident rays have to fall on an object whose surfaces are not parallel, such as a glass prism (triangular shape).
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संबंधित प्रश्न
After tracing the path of a ray of light through a glass prism a student marked the angle of incidence (∠i), angle of refraction (∠r) angle of emergence (∠e) and the angle of deviation (∠D) as shown in the diagram. The correctly marked angles are :

(A) ∠i and ∠r
(B) ∠i and ∠e
(C) ∠i, ∠e and ∠D
(D) ∠i, ∠r and ∠e
Draw a ray diagram to show the dispersion of white light.
State the cause of dispersion of white light
As light rays pass from air into a glass prism, are they refracted towards or away from the normal?
In the formation of spectrum of white light by a prism:
which colour is deviated least?
A beam of white light falls on a glass prism. The colour of light which undergoes the least bending on passing through the glass prism is:
(a) violet
(b) red
(c) green
(d) blue
State the speed of light in (a) air, (b) water, and (c) glass
Which is optically denser: water or air? Give reason
A ray of white light falls on a prism. Draw a ray diagram to show that the prism disperses the white light.
In the spectrum of white light by a prism, the colour at the extreme end opposite to the base of prism is ______.
In the following diagram, the correctly marked angles are
(A) All
(B) Only ∠i and ∠A
(C) ∠i, ∠r and ∠A
(D) ∠i, ∠A and ∠D
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.

Draw a labelled diagram: Dispersion of light through a prism.
How can the presence of ultraviolet radiation be detected?
Write the range of wavelength of the ultraviolet spectrum.
In the figure, a beam of light consisting of three colours blue, red, and yellow is incident on a prism and on a rectangular glass block respectively. Complete the diagram by drawings of the refracted and emergent rays.

The sunlight can be split into its constituent colors using ______.
Curved mirrors have surfaces that are spherical, cylindrical, parabolic, and ellipsoid.
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°:
