question_answer

The magnetic field of a plane electromagnetic wave is given by :

\[\vec{B}={{B}_{0}}\hat{i}[cos(kz-\omega t)]+{{B}_{1}}\hat{j}\cos (kz+\omega t)\] where \[{{B}_{0}}=3\times {{10}^{-5}}T\] and \[{{B}_{1}}=2\times {{10}^{-6}}T.\] The rms  value of the force experienced by a stationary charge \[Q={{10}^{-4}}C\]at \[z=0\]is closest to :         [JEE Main 9-4-2019 Morning]

A)       \[0.9\text{ }N\]

B) \[0.1\text{ }N\]

C) \[3\times {{10}^{2}}N\]

D) \[0.6N\]

Correct Answer: D

Solution :

[d] Maximum Electric field E = [b] [c]

Maximum force

(approx)

Option [d]