A polarizer and an analyzer are oriented so that the maximum amount of lights is transmitted. Fraction of its maximum value is the intensity of the transmitted light reduced when the analyzer is rotated through (intensity of incident light = $I_0$)
a) 30$^\circ$
b)45$^\circ$
c)60$^\circ$
- $0.375\,I_0,0.25\,I_0,0.125\,I_0$
- $0.25\,I_0,0.375\,I_0,0.125\,I_0$
- $0.125\,I_0,0.25\,I_0,0.375\,I_0$
- $0.125\,I_0,0.375\,I_0,0.25\,I_0$
The Correct Option is A
Solution and Explanation
There is no distinction between a polarizer and an analyser; their unique titles are a result of their various optical functions. These are filters that let specific light wave directions flow through them. The analyzer permits light that is parallel to the specimen plane, whereas the polarizer only allows light that is perpendicular to the specimen plane.
Any polarizer turned results in a reduction in transmission intensity. The equation below may be used to quantitatively express this:
I = I0/2Cos2θ
This incident light's intensity is reduced by a factor of two as it passes through a polarizer. Consequently, incident light intensity goes from I0 to I0/2.
By putting θ as 30°, 45°, and 60° the obtained values of Intensity would be – 0.375 I0, 0.25I0, and 0.125I0 respectively.
Unpolarized light is converted into polarised light by a process called as polarisation. Electromagnetic waves are those that are created when an interaction between the magnetic and electric fields occurs.
One definition of polarisation of light is
“A phenomenon that is caused due to the wave nature of electromagnetic radiation is called the polarization of light.”
There are two different kinds of waves:
- Transverse Waves: Transverse waves are those in which the particle motion is perpendicular to the direction of the waves. The rippling of water is a type of transverse wave.
- Longitudinal Waves: These waves are referred to as longitudinal waves when they cause particles of the medium to move in the same direction as the waves.
The interplay of magnetic and electric forces that are travelling across space results in the production of light.
There is an electric field plane, a magnetic field plane that is perpendicular to it, and a direction of light travel that is perpendicular to both of these planes.
In these two domains, light waves vibrate perpendicularly to one another.
A light wave that vibrates in more than one plane is called unpolarized light. Unpolarized light can come from a variety of sources, including sunlight, light from tubes, lamps, and the like.
The other type of wave is a polarised wave, in which only one plane is affected by the vibrations.
All waves in plane-polarized light vibrate in the same direction.
The planes in which the amplitudes occur fluctuate, while the direction of light propagation remains fixed.
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Concepts Used:
Wave Optics
- Wave optics are also known as Physical optics which deal with the study of various phenomena such as polarization, interference, diffraction, and other occurrences where ray approximation of geometric optics cannot be done. Thus, the section of optics that deals with the behavior of light and its wave characteristics is known to be wave optics.
- In wave optics, the approximation is carried out by utilizing ray optics for the estimation of the field on a surface. Further, it includes integrating a ray-estimated field over a mirror, lens, or aperture for the calculation of the transmitted or scattered field.
- Wave optics stands as a witness to a famous standoff between two great scientific communities who devoted their lives to understanding the nature of light. Overall, one supports the particle nature of light; the other supports the wave nature.
- Sir Isaac Newton stood as a pre-eminent figure that supported the voice of particle nature of light, he proposed a corpuscular theory which states that “light consists of extremely light and tiny particles, called corpuscles which travel with very high speeds from the source of light to create a sensation of vision by reflecting on the retina of the eye”.