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प्रश्न
The speed of light varies in different media.
पर्याय
Right
Wrong
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उत्तर
The speed of light varies in different media- Right
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संबंधित प्रश्न
Fill in the following blank with a suitable word:
When light is reflected, the angles of incidence and reflection are ............ .
What are the important differences between looking at a photograph of your face and looking at yourself in a plane mirror?
A wall reflects light and a mirror also reflects light. What difference is three in the way they reflect light?
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?
The angle of reflection is equal to the angle of incidence:
(a) always
(b) sometimes
(c) under special conditions
(d) never
The image formed by a plane mirror is :
(a) virtual, behind the mirror and enlarged.
(b) virtual, behind the mirror and of the same size as the object.
(c) real, at the surface of the mirror and enlarged.
(d) real, behind the mirror and of the same size as the object.
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 from a rarer medium to a denser medium, will it bend towards the normal or away from it?
A ray of light travelling in glass emerges into air. State whether it will bend towards the normal or away from the normal.
State two effects caused by the refraction of light.
When a ray of light passes from air into glass, is the angle of refraction greater than or less than the angle of incidence?
What is meant by 'refraction of light'? Draw a labelled ray diagram to show the refraction of light.
Light travels more quickly through water than through glass.
Which is optically denser : water or glass?
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?
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.
Show the lateral displacement of the ray on the diagram.
State two factors on which the lateral displacement of the emergent ray depends.
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°
What do you understand by refraction of light?
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
A ray of light A incident from air suffers partial reflection and refraction at the boundary of water.
- Complete the diagram showing (i) the reflected ray B and (ii) the refracted ray C.
- How are the angles of incidence i and refraction r related?
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.
Light enters from air to glass having refractive index 1.50. What is the speed of light in the glass? The speed of light in vacuum is 3 × 108 m s−1.
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.
Explain the working of a periscope.
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.
The refractive index of a transparent medium is always greater than ______.
The deviation of light ray from its path when it travels from one transparent medium to another transparent medium is called ______.
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?
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 ratio of the sine of the angle of incidence to the sine of ______ is constant.
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 bottom of swimming pool appears to be less deep than the actual one because of
