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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 |
Fill in the following blank with a suitable word:
When light is reflected, the angles of incidence and reflection are ............ .
A ray of light strikes a plane mirror such that its angle of incidence is 30°. What angle does the reflected ray make with the mirror surface?
Write the word AMBULANCE as it would appear when reflected in a plane mirror. Why is it sometimes written in this way (as its mirror image) on the front of an ambulance?
A boy with a mouth 5 cm wide stands 2 m away from a plane mirror. Where is his image and how wide is the image of his mouth?
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:
- Incident ray
- Point of incidence
- Normal
- Reflected ray
- Angle of incidence
- Angle of reflection
The figure given alongside shows the image of a clock as seen in a plane mirror. The correct time is:

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?
A ray of light travelling in glass emerges into air. State whether it will bend towards the normal or away from the normal.
A ray of light passes from air into a block of glass. Does it bend towards the normal or away from it?
Which phenomenon of light makes the water to appear shallower than it really is?
State whether the following statement is true or false:
Refraction occurs because light slows down in denser materials.
Fill in the following blank with suitable word:
Light travelling along a normal is ...............refracted.
How does the light have to enter the glass:
to produce a large amount of bending?
How does the light have to enter the glass:
for no refraction to happen?
When a ray of light travels from air to glass, it bends .......... the normal.
Fill in the blank and Explain the completed sentences.
The change in ______ of light rays while going from one medium to another is called refraction.
Choose and write the correct option.
If we gradually increase the angle of incidence of a ray of light passing through prism then …..
List in proper sequence the steps of the experiment for determining the approximate focal length of a given concave mirror by obtaining the image of a distant object.
The phenomenon of change in the direction of light when it passes from one transparent medium to another is called ___________.
A real image is formed by the light rays after reflection or refraction when they:
- actually meet or intersect with each other.
- actually converge at a point.
- appear to meet when they are produced in the backward direction.
- appear to diverge from a point.
Which of the above statements are correct?
The laws of reflection hold true for ______.
Lights of different colours are used as signal for safety transport. From these, the wavelength of red light is _______ nm.
Light changes its direction when going from one transparent medium to another transparent medium. This is called _______.
Right or wrong sentence.
The incident rays and refracted rays are on opposite sides of the column.
Observe the given figure and name the following.

| Ray AB | |
| Ray NM | |
| Ray MD | |
| ∠ r |
If a beam of red light and a beam of violet light are incident at the same angle on the inclined surface of a prism from air medium and produce angles of refraction r and v respectively, which of the following is correct?

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.
Which object use the reflection of light?
A water tank appears shallower when it is viewed from the top due to refraction.
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 ______.
A ray of light starting from diamond is incident on the interface separating diamond and water. Draw a labelled ray diagram to show. the refraction of light in this case.
