Electromagnetic Waves - Result Question 3

«««< HEAD:content/english/neet-pyq-chapterwise/physics/electromagnetic-waves/electromagnetic-waves-result-question-3.md

3. In an electromagnetic wave in free space the root mean square value of the electric field is $E _{rms}=6 V / m$. The peak value of the magnetic field is :-

======= ####3. In an electromagnetic wave in free space the root mean square value of the electric field is $E _{rms}=6 V / m$. The peak value of the magnetic field is :-

3e0f7ab6f6a50373c3f2dbda6ca2533482a77bed:content/english/neet-pyq-chapterwise/physics/electromagnetic-waves/electromagnetic-waves—result-question-3.md (a) $2.83 \times 10^{-8} T$

(b) $0.70 \times 10^{-8} T$

(c) $4.23 \times 10^{-8} T$

(d) $1.41 \times 10^{-8} T$

[2017]

Show Answer

Answer:

Correct Answer: 3. (a)

Solution:

  1. (a) Given, $E _{rms}=6 V / m$

$\frac{E _{rms}}{B _{rms}}=c$

$\Rightarrow B _{rms}=\frac{E _{rms}}{c}$

$B _{rms}=\frac{B_0}{\sqrt{2}} \Rightarrow B_0=\sqrt{2} B _{rms}$

$B_0=\sqrt{2} \times \frac{E _{rms}}{c}$ From equation (i)

$=\frac{\sqrt{2} \times 6}{3 \times 10^{8}}=2.83 \times 10^{-8} T$