Question

In an electromagnetic wave in free space, the root mean square value of the electric field is $E_{rms}=6V{m}^{-1}$. The peak value of the magnetic field is

• A. $2.83\times {10}^{-8}T$
• B. $0.70\times {10}^{-8}T$
• C. $4.23\times {10}^{-8}T$
• D. $1.41\times {10}^{-8}T$

Answer 1

The correct option is A $2.83\times {10}^{-8}T$

Given,
$E_{rms}=6V{m}^{-1}\frac{E_{rms}}{B_{rms}}=c{B}_{rms}=\frac{6}{3\times {10}^8}=2\times {10}^{-8}TSince,B_{rms}=\frac{B_0}{\sqrt{2}}{B}_0=B_{rms}\times \sqrt{2}=2.83\times {10}^{-8}T$