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Question
Answer the following question in detail.
State the conditions under which a rainbow can be seen.
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Solution
A rainbow can be observed when there is a light shower with a relatively large raindrop occurring during morning or evening time with enough sunlight around.
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RELATED QUESTIONS
Fill in the blank:
Very fine particles mainly scatter ………… colored light.
Name the phenomenon responsible for it.
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Show with the help of a diagram, how unpolarised light from Sun gets linearly polarised by scattering.
What is linearly polarized light?
A convex lens is made of a material having refractive index
\[1 \cdot 2\] Both the surfaces of the lens are convex. If it is dipped into water (μ = 1.33), it will behave like
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Very fine particles mainly scatter ______ light.
Answer the following question in detail.
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Answer the following question in detail.
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A parallel beam of light of wavelength 5890 Å falls normally on a slit of width 0.2 mm. Find the distance between the first minima on the two sides of the central maximum of the diffraction pattern observed on a screen placed in the focal plane of a convex lens of focal length 50 cm. The lens is placed quite close to the slit.
| Case study: Mirage in deserts |
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To a distant observer, the light appears to be coming from somewhere below the ground. The observer naturally assumes that light is being reflected from the ground, say, by a pool of water near the tall object. Such inverted images of distant tall objects cause an optical illusion to the observer. This phenomenon is called mirage. This type of mirage is especially common in hot deserts. Based on the above facts, answer the following question : |
A diver at a depth 12 m inside water `(a_(µω) = 4/3)` sees the sky in a cone of semi-vertical angle

