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प्रश्न
Write scientific reason.
The coin disappears in a vessel as it is seen from a specific location. But as soon as the water is poured into the vessel to a certain level, the coin appears.
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उत्तर
- Light rays coming from the coin emerge out of water and change their direction due to the refraction of light.
- Hence, as soon as the water is poured into the pot to a certain level, the coin appears.
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संबंधित प्रश्न
If an object is placed at a distance of 10 cm in from of a plane mirror, how far would it be from its image?
Which property of light makes a pencil cast a shadow when it is held in front of a light source?
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Where is the image when you look at something in a mirror?
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What type of reflection of light takes place from a cinema screen?
The boy walks towards the mirror at a speed of 1 m/s. At what speed does his image approach him?
What is meant by 'reflection of light'?
Define the following terms used in the study of reflection of light by drawing a labelled ray-diagram:
(a) Incident ray
(b) Point of incidence
(c) Normal
(d) Reflected ray
(e) Angle of incidence
(f) Angle of reflection
Explain why, though both a plane mirror and a sheet of paper reflect light but we can see the image of our face in a plane mirror but not in a sheet of paper.
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(a) always
(b) sometimes
(c) under special conditions
(d) never
If a ray of light goes form a denser medium to a rarer medium, will it bend towards the normal or away from the normal?
State two effects caused by the refraction of light.
What is meant by 'refraction of light'? Draw a labelled ray diagram to show the refraction of light.
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What is the angle of refraction?
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Match the Following
| Column A | Column B |
| (a) white Light | (1) Convex mirror |
| (b) Refraction | (2) Concave mirror |
| (c) Virtual images | (3) refraction |
| (d) Real images | (4) spectrum |
| (e) Prism | (5) ray of light from glass to air |
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Write scientific reason.
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State whether true or false. If false, correct the statement.
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Assertion and reasoning type
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Her friend noted the following observations from this demonstration:
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