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प्रश्न
The incident rays and refracting rays are on opposite sides of the normal.
पर्याय
Right
Wrong
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उत्तर
The incident rays and refracting rays are on opposite sides of the normal- Right
APPEARS IN
संबंधित प्रश्न
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.
A ray of light strikes a plane mirror such that its angle of incidence is 30°. What angle does the reflected ray make with the mirror surface?
The letter F is placed in front of a plane mirror:
How would its image look like when seen in a plane mirror?
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 are the important differences between looking at a photograph of your face and looking at yourself in a plane mirror?
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 figure given alongside shows the image of a clock as seen a plane mirror. The correct time is:
Figure
(a) 2.25
(b) 2.35
(c) 6.45
(d) 9.25
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?
Explain how to read the following message which was found on some blotting paper:
State two effects caused by the 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?
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.
A coin in a glass tumbler appears to rise as the glass tumbler is slowly filled with water. Name the phenomenon responsible for this effect.
State two factors on which the lateral displacement of the emergent ray depends.
The speed of light is more in glass than in water.
Air is optically .......... than glass.
What do you understand by refraction of light?
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.
Fill in the blank and Explain the completed sentences.
The change in ______ of light rays while going from one medium to another is called refraction.
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 .
Write scientific reason.
The bottom of a pond appears raised.
Write 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.
Observe the given figure and write appropriate phenomenon of light in the box.
State whether true or false. If false, correct the statement.
The angle of deviation depends on the refractive index of the glass.
Why does a ray of light bend when it travels from one medium to another?
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.
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
The angle of incidence for a ray of light having zero reflection angle 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.
Which object use the reflection of light?
When light passes from one medium to another the ray gets bent. This property of light is called ______.
How does the light travel?
Light travels fastest in a vacuum. Why?
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 ______.
Under what circumstances there won’t be any refraction of light when it enters from one medium to another?
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 |
