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प्रश्न
Observe the given diagram and answer the questions:
- Name the process shown in the figure.
- Name the colour that deviates the most.
- Name the colour that deviates the least.
- Name any one phenomenon in nature which is based on the above process.
- Define ‘spectrum’.
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उत्तर
- The process shown in the figure is the dispersion of light.
- The colour that deviates the most is violet.
- The colour that deviates the least is red.
- One phenomenon in nature based on the above process is the formation of a rainbow.
- A spectrum is a band of colours, as seen in a rainbow, produced by the separation of the components of light by their different degrees of refraction according to wavelength.
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संबंधित प्रश्न
In the following diagram, the path of a ray of light passing through a glass prism is shown:
In this diagram the angle of incidence, the angle of emergence and the angle of deviation respectively are (select the correct option):
(A) X, R and T
(B) Y, Q and T
(C) X, Q and P
(D) Y, Q and P
Study the following diagrams in which the path of a ray of light passing through a glass prism as traced by four students P, Q, R and S is shown:
The student who has traced the path correctly is
(A) P
(B) Q
(C) R
(D) S
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
The seven colours in the spectrum of sunlight in order, are represented as :
What conclusion do you draw about the nature of white light in part (b)?
When a white light ray falls on a prism, the ray at its first surface suffers ______.
In which of the following four diagrams is the correct path of a ray of light passing through a glass prism shown ?
In an experiment to trace the path of a ray of light through a glass prism for different values of angle of incidence a student would find that the emergent ray:
(A) is parallel to the incident ray
(B) perpendicular to the incident ray
(C) is parallel to the refracted ray
(D) bends at an angle to the direction of incident ray
A student has to trace the path of a ray of light through a glass prism. List four precautions he should observe for better results.
How can the presence of ultraviolet radiation be detected?
State two properties of ultra-violet radiations which differ from visible light.
Distinguish between an impure spectrum and a pure spectrum.
Write the range of wavelength of the infrared 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.
State the correct sequence (1-7) of colours in the spectrum formed by the prisms A and B, shown in the following figure.
______ 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°:
Make a rainbow
Try to make your own rainbow. You can try this project in the morning or in the evening. Stand with your back towards the Sun. Take a hosepipe or a water pipe used in the garden. Make a fine spray in front of you. You can see different colours of rainbow in the spray.
