Question

A plane electromagnetic wave travels in vacuum along z-direction. What can you say about the directions of its electric and magnetic field vectors? If the frequency of the wave is 30 MHz, what is its wavelength?

Answer 1

\(\overrightarrow E\) and \(\overrightarrow B\) are in x-y plane and are mutually perpendicular. Given v = 30 MHz = 30 × 10⁶ Hz, c = 3 × 10⁸ ms^-1

∴ \(\frac{c}{v}=\frac{3\times10^8}{30\times10^6}\) ^{= 10m}