Advertisements
Advertisements
प्रश्न
Explain why, though both a plane mirror and a sheet of paper reflect light but we can see the image of our face in a plane mirror but not in a sheet of paper.
उत्तर
This is because there occurs regular reflection from a plane mirror, which has a smooth surface. Since the particles of the smooth surface are facing one direction, a beam of parallel light rays falling on it is reflected as a beam of parallel light rays in one direction only. These rays meet when produced backwards to form a virtual image of the light source.
However, in the case of a rough paper, a parallel beam of incident light is reflected in different directions (diffused reflection). So, the light rays don't meet to form an image of the object.
APPEARS IN
संबंधित प्रश्न
Write all the capital letters of the alphabet which look the same 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 ray of light travelling in glass emerges into air. State whether it will bend towards the normal or away from the normal.
What is meant by the 'angle of incidence' and the 'angle of refraction' for a ray of light?
A vertical ray of light strikes the horizontal surface of some water:
What is the angle of incidence?
What do you understand by refraction of light?
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.
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.
A star appears twinkling into the sky because of the reflection of light by the atmosphere.
Why a pencil partly immersed in water appears to be bent at the water surface.
