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प्रश्न
Identify the wrong figure from the following.
पर्याय
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उत्तर
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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 ............ .
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.
Where is the image when you look at something in a mirror?
What are the important differences between looking at a photograph of your face and looking at yourself in a plane mirror?
The boy walks towards the mirror at a speed of 1 m/s. At what speed does his image approach him?
State the uses of plane mirrors.
The image in a plane mirror is virtual and laterally inverted. What does this statement mean?
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?
Name the phenomenon due to which a swimming pool appears less deep than it really is.
State whether the following statement is true or false:
Refraction occurs because light slows down in denser materials.
What is meant by the ‘angle of incidence’ for a ray of light?
Light travels more quickly through water than through glass.
- Which is optically denser: water or glass?
- If a ray of light passes from glass into water, which way will it bend: towards the normal or away from the normal?
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?
Show the lateral displacement of the ray on the diagram.
Explain with the help of a labelled ray diagram, why a pencil partly immersed in water appears to be bent at the water surface. State whether the bending of pencil will increase or decrease if water is replaced by another liquid which is optically more dense than water. Give reason for your answer.
Light travelling from a denser medium to a rarer medium along a normal to the boundary:
(a) is refracted towards the normal
(b) is refracted away from the normal
(c) goes along the boundary
(d) is not refracted
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°
The speed of light is more in glass than in water.
Light travels at a lower speed in water than in air.
Air is optically .......... than glass.
Define the principal focus of a concave mirror.
List four characteristics of the image formed by a concave lens of focal length 20 cm when the object is placed at a distance of 40 cm from its optical centre.
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.
Write a 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.
What is refractive index?
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.
When light passes from one medium to another the ray gets bent. This property of light is called ______.
Light travels fastest in a vacuum. Why?
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
In refraction of light through a glass slab, the directions of the incident ray and the refracted ray are ______.
