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प्रश्न
During sunset and sunrise, the sun is seen when it is slightly below the horizon. Give reason.
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उत्तर
Light rays from the sun while coming towards earth suffers successive refractions from a rarer to a denser medium and so it bends towards the normal at each refraction. These rays on earth appear to be coming from an apparent position of the sun which is higher than its actual position. Thus, the sun is seen even when it is slightly below the horizon during sunset and sunrise.
संबंधित प्रश्न
Write a relationship between the angle of incidence and angle of refractions for a given pair of media
Name a prism required for obtaining a spectrum of Ultraviolet light.
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What do you understand by the statement the refractive index of glass is 1.5 for white light?
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- 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)?
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A ray of light OP passes through a right angles prism as shown in the adjacent diagram.
(a) State the angles of incidence at the faces AC and BC.
(b) Name the phenomenon which the ray suffers at the face AC.
A ray of light moves from a rare medium to a dense medium as shown in the diagram below. Write down the number of the ray which represents the partially reflected ray.
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A ray of monochromatic light is incident from the air on a glass slab:
(i) Draw a labelled ray diagram showing the change in the path of the ray till it emerges from the glass slab.
(ii) Name the two rays that are parallel to each other.
(iii) Mark the lateral displacement in your diagram.
