NEET Solved Paper 2017 Question 19
Question: 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
Options:
A) $ 4.23\times {10^{-8}}T $
B) $ 1.41\times {10^{-8}}T $
C) $ 2.83\times {10^{-8}}T $
D) $ 0.70\times {10^{-8}}T $
Show Answer
Answer:
Correct Answer: C
Solution:
$ \frac{E _{rms}}{B _{rms}}=c $ $ B _{rms}=\frac{E _{rms}}{c} $ $ =\frac{6}{3\times 10^{8}} $ $ B _{rms}=2\times {10^{-8}} $ $ B _{rms}=\frac{B _0}{\sqrt{2}} $ $ B _0=\sqrt{2}\times B _{rms} $ $ =\sqrt{2}\times 2\times {10^{-8}} $ $ =2.83\times {10^{-8}}T $
