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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
What is refraction of light?
| 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 |
What type of reflection of light takes place from a cinema screen?
State the uses of plane mirrors.
What is meant by 'reflection of light'?
A man stands 10 m in front of a large plane mirror. How far must the walk before he is 5 m away from his image?
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?
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?
A coin in a glass tumbler appears to rise as the glass tumbler is slowly filled with water. Name the phenomenon responsible for this effect.
With the help of a labelled diagram, explain why a tank full of water appears less deep than it actually is.
The depth of a pond when seen from above appears to be less.
When a ray of light travels from water to air, it bends ............. the normal.
The size of image of an object by a convex lens of focal length 20 cm is observed to be reduced to `1/3` rd of its size . Find the distance of the object from the optical centre of the lens .
Due to _______ pencil looks bent in water, in the given experiment.
Identify the wrong figure from the following.
Right or wrong sentence.
The incident rays and refracted rays are on opposite sides of the column.
Write scientific reason.
The sun appears on the western horizon for some time after sunset.
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.
State whether true or false. If false, correct the statement.
The angle of deviation depends on the refractive index of the glass.
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?
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?
A pencil when dipped in water in a glass tumbler appears to be bent at the interface of air and water. Will the pencil appear to be bent to the same extent, if instead of water we use liquids like, kerosene or turpentine. Support your answer with reason.
The phenomenon of light passing through the object is called ______.
When light passes from one medium to another the ray gets bent. This property of light is called ______.
Light bends as it passes from one medium to another. What is this phenomenon called?
A ray of light traveling in medium 1 strikes and travels into another transparent medium 2. If the speed of light is greater in medium 1, the ray will ______.
Under what circumstances there won’t be any refraction of light when it enters from one medium to another?
Match the following:
| Column I | Column II | ||
| 1. | r > 90 | a. | Light gazes at the surface of separation between the two modes. |
| 2. | r = 90 | b. | No refraction. |
| 3. | r < 90 | c. | Refracted ray away from the normal |
The part of light that enters into the other medium and travels in a straight path but in a direction different from its initial direction is called:
When light travels from a rarer medium to a denser medium, its speed:
When a light ray passes from a denser medium to a rarer medium, it bends:
When light travels from a denser medium to a rarer medium, its speed:
According to the first law of refraction, the incident ray, the refracted ray, and the normal at the point of incidence:
According to the second law of refraction, for a given pair of media, the ratio of the sine of the angle of incidence to the sine of the angle of refraction:
In the formula for absolute refractive index \[n = \frac{c}{v}\], the quantity c represents:
