Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R Assertion A: Wave polarization may be regarded as the locus of the tip of the electric field (in a plane perpendicular to the direction of propagation) at a given point as a function of time. Reason R: Elliptical polarization is achieved when the x and y components are not equal in magnitude $E_{ox} \neq E_{oy}$ and the phase difference between them is an odd multiple of $\frac{\pi}{2}$. [z-is the direction of propagation] In the light of the above statements, choose the most appropriate answer from the options given below
Analysis of Assertion A
Assertion A states that wave polarization is the locus traced by the tip of the electric field vector in a plane perpendicular to the direction of propagation, as a function of time.
This definition accurately describes what polarization represents. The electric field vector of a transverse wave (like light or radio waves) oscillates. As the wave propagates, the endpoint of this oscillating vector traces a path. The shape of this path defines the polarization state.
Therefore, Assertion A is correct.
Analysis of Reason R
Reason R provides conditions for achieving elliptical polarization:
- The magnitudes of the x and y components of the electric field ($E_{ox}$ and $E_{oy}$) are not equal ($E_{ox} \neq E_{oy}$).
- The phase difference ($\Delta \phi$) between these components is an odd multiple of $\frac{\pi}{2}$. This means $\Delta \phi = (2n+1)\frac{\pi}{2}$, where $n$ is an integer (e.g., $\frac{\pi}{2}, \frac{3\pi}{2}, \frac{5\pi}{2}, ...$).
These conditions correctly describe elliptical polarization. If the amplitudes were equal ($E_{ox} = E_{oy}$) and the phase difference was an odd multiple of $\frac{\pi}{2}$, it would result in circular polarization. If the phase difference were $0$ or $\pi$, it would result in linear polarization (regardless of amplitude equality).
Therefore, Reason R is correct.
Relationship Between Assertion A and Reason R
Assertion A provides a general definition of wave polarization as the locus of the electric field vector's tip. Reason R describes the specific conditions required to achieve a particular type of polarization, namely elliptical polarization.
While Reason R correctly describes elliptical polarization, it does not explain the fundamental definition of polarization given in Assertion A. Assertion A is about *what* polarization is (the locus), whereas Reason R is about *how* a specific type of polarization (elliptical) is formed.
Thus, both statements are correct individually, but Reason R does not serve as an explanation for Assertion A.
Conclusion
Based on the analysis, both Assertion A and Reason R are correct, but Reason R is not the correct explanation of Assertion A.
The most appropriate answer is Option B: Both A and R are correct but R is NOT the correct explanation of A.
Important Questions from Electromagnetic Wave Propagation
For sky waves, following statements are given:
(A) n > 1, this shows 81 \(\rm\frac{N}{f^2}\) positive
(B) n > 1, show 81 \(\rm\frac{N}{f^2}\) Negative
(C) n < 1 shows 81 \(\rm\frac{N}{f^2}\) < 1
(D) v g x v p= c 2
(E) n = 0 shows 81 \(\rm\frac{N}{f^2}\) = 1, f = f c
Choose the correct answer from the options given below:
If the Polarization vector is given as N and the Direction of propagation is given as K then which one of the following relations is correct?
The wave length (λ) in meters of an electromagnetic wave is related to its frequency (f) in MHz as:
Bending of light wave as it passes between material of different optical density
The wave impedance of a medium is equal to:
