Which one of the following is the property of a monochromatic, plane electromagnetic wave in free space?
1
Electric and magnetic fields have a phase difference of \(\frac{\pi}{2}\)
2
The energy contributions of both electric and magnetic fields are equal
3
The direction of propagation is in the direction of \(\overrightarrow{B}\times\overrightarrow{E}\)
4
The pressure exerted by the wave is the product of its speed and energy density