question_answer

A plane electromagnetic wave having a frequency v = 23.9 GHz propagates along the positive z-direction in free space. The peak value of the electric field is 60 V/m. Which among the following is the acceptable magnetic field component in the electromagnetic wave? [JEE Main 12-4-2019 Afternoon]

A) \[\vec{B}=2\times {{10}^{7}}\sin (0.5\times {{10}^{3}}z+1.5\times {{10}^{11}}t)\hat{i}\]

B) \[\vec{B}=2\times {{10}^{-7}}\sin (1.5\times {{10}^{2}}x+0.5\times {{10}^{11}}t)\hat{j}\]

C) \[\vec{B}=2\times {{10}^{-7}}\sin (0.5\times {{10}^{3}}z-1.5\times {{10}^{11}}t)\hat{i}\]

D) \[\vec{B}=60\sin (0.5\times {{10}^{3}}x+1.5\times {{10}^{11}}t)\hat{k}\]

Correct Answer: C

Solution :

[c] Magnetic field when electromagnetic wave propagates in +z direction

where