š“ Flashcard Mode
Maxwell's Equations and Electromagnetic Waves - Class XI
Card1 / 22
Mastered0
Review0
QuestionClick to flip
Choose the correct answer from the alternatives given.
A plane electromagnetic wave of frequency $25 MHz$ travels in free space along $X$-direction. At a particular point in space and time, electric field $\vec E=6.3\ \hat j\ V/m$. What is $B$ at this point.
AnswerClick to flip back
A
$2.1 \, \times \, 10^{-8} \, T$
š” Explanation:
Given: The frequency of the electromagnetic wave is $25\ MHz$.
The electric field at the particular point is $6.3\hat j\ V/m$
To find: The magnetic field at that point.
The magnetic field of the electromagnetic wave at a point is given by:
$B = \dfrac{E}{c}\= \dfrac{6.3}{3 \times 10^8}\ \Rightarrow2.1 \times 10^{-8} T$
So, option $(D)$ is correct.