i. In an EM wave, the magnetic field and electric field both vary sinusoidally with x.
ii. For a wave travelling along X-axis having \(\overset\rightarrow{E}\) along Y-axis and \(\overset\rightarrow{B}\) along the Z-axis,
Ey = E0 sin (kx – ωt)
Bz = B0 sin (kx – ωt)
where, E0 is the amplitude of the electric field (Ey) and B0 is the amplitude of the magnetic field (Bz).
iii. The propagation constant is given by k = \(\frac{2π}{λ}\) and λ is the wavelength of the wave. The angular frequency of oscillations is given by ω = 2πv, v being the frequency of the wave.
Hence, Ey = E0 sin (\(\frac{2πx}{λ}– 2πvt)\)
Bz = B0 sin (\(\frac{2πx}{λ}– 2πvt)\)
v. Both the electric and magnetic fields attain their maximum or minimum values at the same time and at the same point in space, i.e., \(\overset\rightarrow{E}\) and \(\overset\rightarrow{B}\) oscillate in phase with the same frequency.