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प्रश्न
Write scientific reason.
A pencil appears to be broken near the surface of water.
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उत्तर
- When one look at the portion of the pencil that is inside the water, light travels from water to air via glass.
- This light ray changes the medium and undergoes refraction.
- As a result, the pencil inside the water appears to be broken near the surface of water.
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संबंधित प्रश्न
| Column I | Column II | Column III | |
| 1 | Dispersion | Long-sightedness | Twinkling of stars |
| 2 | Refraction | Splitting of white light into component colours | Convex lens |
| 3 | Hypermetropia | Change in the direction of the ray of light due to change in medium | Spectrum of seven colours |
Name the phenomenon responsible for the following effect:
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Fill in the following blank with a suitable word:
When light is reflected, the angles of incidence and reflection are ............ .
State whether the following statement is true of false:
A student says that we can see an object because light from our eyes is reflected back by the object.
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Write all the capital letters of the alphabet which look the same in a plane mirror.
A man sits in an optician's chair looking into plane mirror which is 2 m away from him and views the image of a chart which faces the mirror and is 50 cm behind his head. How far away from his eyes does the chart appear to be?
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If a ray of light goes from a rarer medium to a denser medium, will it bend towards the normal or away from it?
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?
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Light travels more quickly through water than through glass.
If a ray of light passes from glass into water, which way will it bend : towards the normal or away from the normal?
State two factors on which the lateral displacement of the emergent ray depends.
A ray of light when passes from glass to air, bends towards the normal.
Draw a diagram showing the refraction of a light ray from water to glass. Label on it the incident ray, the angle of incidence (/), and the angle of refraction (r)
Draw suitable diagrams to illustrate how a beam of light incident parallel to the principal axis is reflected by:
(a) a concave mirror, and (b) a convex mirror
Choose and write the correct option.
If we gradually increase the angle of incidence of a ray of light passing through prism then …..
Define the principal focus of a concave mirror.
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.
Observe the given figure and name the following.
| Ray AB | |
| Ray NM | |
| Ray MD | |
| ∠ r |
Observe the given figure and write appropriate phenomenon of light in the box.
Assertion and reasoning type
- Assertion: If the refractive index of the medium is high (denser medium) the velocity of the light in that medium will be small
- Reason: Refractive index of the medium is inversely proportional to the velocity of the light
What is refractive index?
You are given water, mustard oil, glycerine and kerosene. In which of these media a ray of light incident obliquely at same angle would bend the most?
The deviation of light ray from its path when it travels from one transparent medium to another transparent medium is called ______.
The angle of incidence for a ray of light having zero reflection angle is ______.
The angle of incidence from air to glass at the point O on the hemispherical glass slab is.
In the above diagram light is travelling through different media. It is noted by a scientist that ∠1= ∠3 = ∠4 but ∠2 < ∠1. Which of the following statement would be correct?
Which object use the reflection of light?
The bending of light as it passes from one medium to another is called ______.
A water tank appears shallower when it is viewed from the top due to refraction.
Under what circumstances there won’t be any refraction of light when it enters from one medium to another?
The bottom of swimming pool appears to be less deep than the actual one because of
In refraction of light through a glass slab, the directions of the incident ray and the refracted ray are ______.
