JEE Main 2022 — Physics Electromagnetism
Given below two statements : One is labelled as Assertion (A) and other is labelled as Reason (R).
Assertion (A): Non-polar materials do not have any permanent dipole moment.
Reason (R): When a non-polar material is placed in an electric field, the centre of the positive charge distribution of it's individual atom or molecule coincides with the centre of the negative charge distribution.
In the light of above statements, choose the most appropriate answer from the options given below.
Held on 26 Jun 2022 · Verified 6 Jul 2026.
Both (A) and (R) are correct and (R) is the correct explanation of (A).
Both (A) and (R) are correct and (R) is not the correct explanation of (A).
(A) is correct but (R) is not correct.
(A) is not correct but (R) is correct.
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A magnetic field vector in an electromagnetic wave is represented by $\vec{B}=B_0\sin\left(2\pi vt-\dfrac{2\pi x}{\lambda}\right)\hat{j}$. Its associated electric field vector is ______.
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A charged particle moves in a uniform magnetic field. If the velocity is perpendicular to the field, the path of the particle is:
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An electromagnetic wave of frequency 100 MHz propagates through a medium of conductivity, $\sigma=10 \mathrm{mho} / \mathrm{m}$. The ratio of maximum conduction current density to maximum displacement current density is $\_\_\_\_$. $\left[\text{Take }\frac{1}{4 \pi \epsilon_{\mathrm{o}}}=9 \times 10^{9} \mathrm{Nm}^{2} / \mathrm{C}^{2}\right]$
Work through every JEE Main Electromagnetism PYQ, year by year.