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प्रश्न
What is meant by 'reflection of light'?
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उत्तर
The process of sending back light rays that fall on the surface of an object is called reflection of light.
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संबंधित प्रश्न
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?
What is the difference between regular reflection of light and diffuse reflection of light?
State and explain the laws of reflection of light at a plane surface (like a plane mirror), With the help of a labelled ray-diagram. Mark the angles of 'incidence' and 'reflection' clearly on the diagram. If the angle of reflection is 47.5°, what will be the angle of incidence?
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 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 ray of light strikes a plane mirror PQ at an angle of incidence of 30°, is reflected from the plane mirror and then strikes a second plane mirror QR placed at right angles to the first mirror. The angle of reflection at the second mirror is ______.
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.
Why does a ray of light bend when it travels from one medium to another?
What is meant by ‘refraction of light’?
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?
Name the phenomenon due to which a pencil partly immersed in water and held obliquely appears to be bent at the water surface.
A vertical ray of light strikes the horizontal surface of some water:
- What is the angle of incidence?
- What is the angle of refraction?
A vertical ray of light strikes the horizontal surface of some water:
What is the angle of refraction?
A ray of light when passes from glass to air, bends towards the normal.
Light travels at a lower speed in water than in 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)
The diagram (figure) given below shows two parallel rays 1 and 2 incident on (a) a concave mirror, (b) a convex mirror. Draw the reflected rays and mark the focus by the symbol F.
What is the cause of refraction of light when it passes from one medium to another?
A light ray suffers reflection and refraction at the boundary in passing from air to water. Draw a neat labelled ray diagram to show it.
The laws of reflection hold true for ______.
Light changes its direction when going from one transparent medium to another transparent medium. This is called _______.
The incident rays and refracting rays are on opposite sides of the normal.
Write scientific reason.
A pencil appears to be broken near the surface of water.
Observe the given figure and write appropriate phenomenon of light in the box.
Numerical problems.
The speed of light in water is 2.25 × 108 ms–1. If the speed of light in vacuum is 3 × 108 ms–1, calculate the refractive index of water.
The refractive index of a transparent medium is always greater than ______.
Assertion and reasoning type
- Assertion: If the refractive index of the medium is high (denser medium) the velocity of the light in that medium will be small
- Reason: Refractive index of the medium is inversely proportional to the velocity of the light
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?
The angle of incidence from air to glass at the point O on the hemispherical glass slab is.
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?
Noor, a young student, was trying to demonstrate some properties of light in her Science project work. She kept ‘X’ inside the box (as shown in the figure) and with the help of a laser pointer made light rays pass through the holes on one side of the box. She had a small butter-paper screen to see the spots of light being cast as they emerged.
Her friend noted the following observations from this demonstration:
- Glass is optically rarer than air.
- Air and glass allow light to pass through them with the same velocity.
- Air is optically rarer than glass.
- Speed of light through a denser medium is faster than that of a rarer medium.
- The ratio: sin of angle of incidence in the first medium to the ratio of sin of angle of refraction in the second medium, gives the refractive index of the second material with respect to the first one.
Which one of the combinations of the above statements given below is correct.
Light bends as it passes from one medium to another. What is this phenomenon called?
A ray of light traveling in medium 1 strikes and travels into another transparent medium 2. If the speed of light is greater in medium 1, the ray will ______.
The ratio of the sine of the angle of incidence to the sine of ______ is constant.
Mirage is an example of refraction and the total internal reflection of light.
Under what circumstances there won’t be any refraction of light when it enters from one medium to another?
