Question

In an electromagnetic wave the $rms$ value of field is $100V/m$. Find intensity of the wave

• A. $30.2W/m^2$
• B. $15.3W/m^2$
• C. $26.5W/m^2$
• D. $13.27W/m^2$

Answer 1

The correct option is D $13.27W/m^2$

$I=\frac{1}{2}{\in }_o{E}_{rms}^{2}C$

$=\frac{1}{2}\times 8.85\times {10}^{-12}\times (100{)}^2\times 3\times {10}^8$

$I=13.27$ watt.