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प्रश्न
Choose and write the correct option.
If we gradually increase the angle of incidence of a ray of light passing through prism then …..
पर्याय
Angle of deviation goes on decreasing.
Angle of deviation decreases but after certain value of incident angle, deviation angle increases
Angle of deviation goes on increasing.
Angle of deviation increases but after certain value of incident angle deviation angle decreases.
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उत्तर
Angle of deviation decreases but after certain value of
incident angle, deviation angle increases.
APPEARS IN
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 |
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.
An extended object in the form of an arrow pointing upward has been placed in front of a plane mirror. Draw a labelled ray-diagram to show the formation of its image.
With the help of a labelled ray-diagram, describe how a plane mirror forms an image of a point source of light placed in front of it. State the characteristics of the image formed in a plane mirror.
The image in a plane mirror is virtual and laterally inverted. What does this statement mean?
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?
Explain how to read the following message which was found on some blotting paper:
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?
As light rays pass from water into glass, are they refracted towards the normal or away from the normal?
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.
A ray of light travelling in air is incident on a rectangular glass block and emerges out into the air from the opposite face. Draw a labelled ray diagram to show the completer path of this ray of light. Mark the two points where the refraction of light takes place. What can you say about the final direction of ray of light?
What is meant by the ‘angle of incidence’ for a ray of light?
When a light ray passes from air into glass, what happens to its speed? Draw a diagram to show which way the ray of light bends.
Name the phenomenon due to which a pencil partly immersed in water and held obliquely appears to be bent at the water surface.
Show the lateral displacement of the ray on the diagram.
When a ray of light travelling in glass enters into water obliquely:
(a) it is refracted towards the normal
(b) it is not refracted at all
(c) it goes along the normal
(d) it is refracted away from the normal
A ray of light passes from a medium X to another medium Y. No refraction of light occurs if the ray of light hits the boundary of medium Y at an angle of:
(a) 0°
(b) 45°
(c) 90°
(d) 120°
A vertical ray of light strikes the horizontal surface of some water:
What is the angle of refraction?
How does the light have to enter the glass:
for no refraction to happen?
Water is optically .......... than air.
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
What is the cause of refraction of light when it passes from one medium to another?
A small air bubble in a glass block when seen from above appears to be raised because of ______.
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.
What is atmospheric reflection? Explain with the help of a labelled diagram that the position of a star as seen by us is not its true position.
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 .
Identify the wrong figure from the following.
The speed of light varies in different media.
Write scientific reason.
The bottom of a pond appears raised.
Explain with diagrams how refraction of incident light takes place from
- rarer to denser medium
- denser to rarer medium
- normal to the surface separating the two media.
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 surface will not reflect most of the light falling on them?
Light travels fastest in a vacuum. Why?
The bending of light as it passes from one medium to another is called ______.
Why a pencil partly immersed in water appears to be bent at the water surface.
