Advertisements
Advertisements
Question
What type of reflection of light takes place from a cinema screen?
Advertisements
Solution
Diffuse reflection of light takes place from a cinema screen.
APPEARS IN
RELATED QUESTIONS
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?
What is meant by 'reflection of light'?
The image in a plane mirror is virtual and laterally inverted. What does this statement mean?
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 form a denser medium to a rarer medium, 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.
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.
The speed of light is more in glass than in water.
Image is formed by a mirror due to refraction of light.
A small air bubble in a glass block when seen from above appears to be raised because of ______.
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 .
A real image is formed by the light rays after reflection or refraction when they:
- actually meet or intersect with each other.
- actually converge at a point.
- appear to meet when they are produced in the backward direction.
- appear to diverge from a point.
Which of the above statements are correct?
The incident rays and refracting rays are on opposite sides of the normal.
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
What is refractive index?
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.
When light passes from one medium to another the ray gets bent. This property of light is called ______.
