Advertisements
Advertisements
प्रश्न
(a) A ray of monochromatic light enters glass PQRS as shown in the fig. Complete the path of ray till it emerges from the glass. (Critical angle of glass is 420).
(b) Draw diagram of a prism periscope.
(c) What are the advantages of total internal reflecting prism over plane mirror?
Advertisements
उत्तर
Note : here that when the angle of incidence in the denser medium is more than the critical angle (= 42), then the ray undergoes total internal reflection.
At angle of incidence equal to critical angle, the ray grazes the interface.
(b) Diagram of prism periscope:
(c) In case of reflection from plane mirror, all of light in not reflected. In case of total reflecting prism, all rays failing beyond critical angle will be totally reflected. The intensity of reflected light is equal to the intensity of incident light in case of total internal ref;lection but not in case of reflection from plane mirror.
In addition, the reflection through a thick mirror causes multiple image formation as well as lateral inversion of image.
Due to the above two reasons, the total reflecting prisms are preferred over the plane mirrors.
APPEARS IN
संबंधित प्रश्न
The figure shows a ray of light falling normally on the face AB of an equilateral glass prism having refractive index`3/2`, placed in water of refractive index `4/3`.Will this ray suffer total internal reflection on striking the face AC? Justify your answer.
What is total internal reflection?
Two isosceles right-angle glass prisms P and Q are placed near each other as shown in Fig. Complete the path of the light ray entering the prism P till it emerges out of the prism Q.
A ray of light is incident on a glass surface at an angle of 50° with the corresponding angle of refraction 30°. Find the value of the R.I. of glass.
Choose the correct option.
Select the WRONG statement.
Choose the correct option.
Angles of deviation for extreme colours are given for different prisms. Select the one having maximum dispersive power of its material.
The resultant `vec"R"` of `vec"P"` and `vec"Q"` is perpendicular to `vec"P"`. Also `|vec"P"|=|vec"R"|`. The angle between `vec"P"` and `vec"Q"` is ______.
[tan 45° = 1]
A green light is incident from the water to the air-water interface at the critical angle (C). Select the correct statement.
Optical Fibres are based on the phenomenon of dispersion.
A ray of light incident at an angle θ on a refracting face of a prism emerges from the other face normally. If the angle of the prism is 5° and the prism is made of a material of refractive index 1.5, the angle of incidence is ______.
