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प्रश्न
State two uses of Polaroid.
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उत्तर
Uses of Polaroid:-
(1) In motor car head lights – To remove headlight glare
(2) To improve color contrast in old oil paintings
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संबंधित प्रश्न
With the help of neat diagram, explain how non-polar dielectric material is polarised in external electric field of increasing intensity. Define polarisation in dielectrics.
For a glass plate as a polariser with refractive index 1.633, calculate the angle of incidence at which light is polarised.
Show, using a simple polaroid, that light waves are transverse in nature. Intensity of light coming out of a polaroid does not change irrespective of the orientation of the pass axis of the polaroid. Explain why.
Show, with the help of a diagram, how unpolarised sunlight gets polarised due to scattering.
Two polaroids P1 and P2 are placed with their pass axes perpendicular to each other. An unpolarised light of intensity Io is incident on P1. A third polaroid P3 is kept in between P1 and P2 such that its pass axis makes an angle of 45° with that of P1. Determine the intensity of light transmitted through P1, P2 and P3
Two polaroids P1 and P2 are placed with their pass axes perpendicular to each other. An unpolarised light of intensity I0 is incident on P1. A third polaroid P3 is kept in between P1 and P2 such that its pass axis makes an angle of 30° with that of P1. Determine the intensity of light transmitted through P1, P2 and P3
What is the Brewster angle for air to glass transition? (Refractive index of glass = 1.5)
A ray of light passes from a vacuum to a medium of refractive index (μ). The angle of
incidence is found to be twice the angle of refraction. The angle of incidence is _______.
A) `cos^(-1)(mu/2)`
B) cos−1(μ)
C) `2 cos^(-1) (mu/2)`
D) `2 sin^(-1) (mu/2)`
The glass plate of refractive index 1.732 is to be used as a polarizer, its polarising angle is _______.
Show using a proper diagram how unpolarised light can be linearly polarised by reflection from a transparent glass surface.
With the help of an experiment, state how will you identify whether a given beam of light is polarised or unpolarized?
Which of the following properties shows that light is a transverse wave?
A beam of light is incident at the polarizing angle of 35° on a certain glass plate. The refractive index of the glass plate is :
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?
What is polarisation?
What is a analyser?
What is unpolarised light?
What is partially polarised light?
State Brewster’s law.
How is polarisation of light obtained by scattering of light?
What is normal focusing?
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.
A plane mirror produces a magnification of
Figure shown a two slit arrangement with a source which emits unpolarised light. P is a polariser with axis whose direction is not given. If I0 is the intensity of the principal maxima when no polariser is present, calculate in the present case, the intensity of the principal maxima as well as of the first minima.
To ensure almost 100 per cent transmissivity, photographic lenses are often coated with a thin layer of dielectric material. The refractive index of this material is intermediated between that of air and glass (which makes the optical element of the lens). A typically used dielectric film is MgF2 (n = 1.38). What should the thickness of the film be so that at the center of the visible spectrum (5500 Å) there is maximum transmission.
A polarizer - analyser set is adjusted such that the intensity of light coming out of the analyser is just 10% of the original intensity. Assuming that the polarizer - analyser set does not absorb any light, the angle by which the analyser need to be rotated further to reduce the output intensity to be zero, is ______.
