Advertisements
Advertisements
प्रश्न
Show, via a suitable diagram, how unpolarised light can be polarised by reflection.
Advertisements
उत्तर
An ordinary beam of light on reflection from a transparent medium becomes partially polarised. The degree of polarisation increases as the angle of incidence is increased. At a particular value of angle of incidence, the reflected beam becomes completely polarised. This angle of incidence is called the polarising angle (p).
When light is incident at polarising angle at the interface of a refracting medium, the refractive index of the medium is equal to the tangent of the polarising angle.
μ = tan p
where
μ → Refractive index of the refracting medium
p → Polarising angle
APPEARS IN
संबंधित प्रश्न
What is a Polaroid?
The refractive indices of water for red and violet colours are 1.325 and 1.334 respectively.
Find the difference between the velocities of rays for these two colours in water. (c = 3 × 108 m/s)
The glass plate of refractive index 1.732 is to be used as a polarizer, its polarising angle is _______.
With the help of an experiment, state how will you identify whether a given beam of light is polarised or unpolarized?
Green light is incident at the polarising angle on a certain transparent medium. The angle of refraction is 30° . Find
(i) polarising angle, and
(ii) refractive index of the medium.
What is the difference between polarised light and unpolarised light?
A ray of ordinary light is travelling in air. It is incident on air glass pair at a polarising angle of 56°. Find the angle of refraction in glass.
The reflected light is found to be plane polarised when an unpolarized light falls on a denser medium at 60° with the normal. Find the angle of refraction and critical angle of incidence for total internal reflection in the denser to rarer medium reflection.
Which of the following phenomena is not common to sound and light waves?
Consider a light beam incident from air to a glass slab at Brewster’s angle as shown in figure. A polaroid is placed in the path of the emergent ray at point P and rotated about an axis passing through the centre and perpendicular to the plane of the polaroid.
