Advertisements
Advertisements
प्रश्न
Which property of light makes a pencil cast a shadow when it is held in front of a light source?
Advertisements
उत्तर
One property of light that makes a pencil cast a shadow when it is held in front of it is that light travels in a straight line.
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?
Define the following terms used in the study of reflection of light by drawing a labelled ray-diagram:
(a) Incident ray
(b) Point of incidence
(c) Normal
(d) Reflected ray
(e) Angle of incidence
(f) Angle of reflection
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?
The image of an object formed by a plane mirror is:
(a) virtual
(b) real
(c) diminished
(d) upside-down
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?
Why does a ray of light bend when it travels from one medium to another?
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?
What is meant by the 'angle of incidence' and the 'angle of refraction' for a ray of light?
Match the Following
| Column A | Column B |
| (a) white Light | (1) Convex mirror |
| (b) Refraction | (2) Concave mirror |
| (c) Virtual images | (3) refraction |
| (d) Real images | (4) spectrum |
| (e) Prism | (5) ray of light from glass to air |
Draw suitable diagrams to illustrate how a beam of light incident parallel to the principal axis is reflected by:
(a) a concave mirror, and (b) a convex mirror
What is the cause of refraction of light when it passes from one medium to another?
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.
List in proper sequence the steps of the experiment for determining the approximate focal length of a given concave mirror by obtaining the image of a distant object.
Observe the given figure and name the following.

| Ray AB | |
| Ray NM | |
| Ray MD | |
| ∠ r |
State whether true or false. If false, correct the statement.
The angle of deviation depends on the refractive index of the glass.
Explain with diagrams how refraction of incident light takes place from
- rarer to denser medium
- denser to rarer medium
- normal to the surface separating the two media.
A pencil when dipped in water in a glass tumbler appears to be bent at the interface of air and water. Will the pencil appear to be bent to the same extent, if instead of water we use liquids like, kerosene or turpentine. Support your answer with reason.
How do twinkling stars occur? (or) what is the cause of the twinkling of stars?
In refraction of light through a glass slab, the directions of the incident ray and the refracted ray are ______.
