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प्रश्न
Lights of different colours are used as signal for safety transport. From these, the wavelength of red light is _______ nm.
पर्याय
400
500
600
700
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उत्तर
Lights of different colours are used as signal for safety transport. From these, the wavelength of red light is 700 nm.
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संबंधित प्रश्न
What is refraction of light?
Which property of light makes a pencil cast a shadow when it is held in front of a light source?
Fill in the following blank with a suitable word:
When light is reflected, the angles of incidence and reflection are ............ .
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How would its image look like when seen 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?
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.
Write all the capital letters of the alphabet which look the same in a plane mirror.
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(a) virtual
(b) real
(c) diminished
(d) upside-down
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 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 goes from water into air. Will it bend towards the normal or away from the normal?
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Light travelling along a normal is ...............refracted.
Fill in the following blank with suitable word:
Light bends when is passes from water into air. We say that it is ............
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?
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.
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What is the angle of incidence?
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What is the angle of refraction?
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Observe the given figure and write appropriate phenomenon of light in the box.
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Assertion and reasoning type
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Which object use the reflection of light?
Which surface will not reflect most of the light falling on them?
Assertion: The air bubble shines in water.
Reason: Air bubble shines due to the refraction of light.
How do twinkling stars occur? (or) what is the cause of the twinkling of stars?
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