Advertisements
Advertisements
प्रश्न
State the uses of plane mirrors.
Advertisements
उत्तर
Uses of a plane mirror:
- Plane mirrors are used to see ourselves. Example, mirrors in a bathroom.
- Plane mirrors are fixed on the inner walls of certain shops ( like jewellery shops) to make them look bigger.
- Plane mirrors are fitted at blind turns of some busy roads so that drivers can see the vehicles coming from the other side and prevent accidents.
- Plane mirrors are used in periscopes.
APPEARS IN
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?
Write all the capital letters of the alphabet which look the same in a plane mirror.
The image of an object formed by a plane mirror is:
(a) virtual
(b) real
(c) diminished
(d) upside-down
Explain how to read the following message which was found on some blotting paper:
A ray of light goes from water into air. Will it bend towards the normal or away from the normal?
Fill in the following blank with suitable word:
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?
Image is formed by a mirror due to refraction of light.
Water is optically .......... than 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)
A small air bubble in a glass block when seen from above appears to be raised because of ______.
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.
Observe the given figure and name the following.

| Ray AB | |
| Ray NM | |
| Ray MD | |
| ∠ r |
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 bending of light as it passes from one medium to another is called ______.
A star appears twinkling into the sky because of the reflection of light by the atmosphere.
A water tank appears shallower when it is viewed from the top due to refraction.
Why a pencil partly immersed in water appears to be bent at the water surface.
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 |
