The electric field part of an electromagnetic wave in a medium is represented by Ex = 0
Ey = 2.5 (N / C) cos [(2π x 10⁶ rad/m) t – (π x 10⁻² rad/s) x ];
Ez = 0. The wave is:

Options

(a) moving along x direction with frequency 10⁶ Hz and wavelength 100 m.
(b) moving along x direction with frequency 10⁶ Hz and wave length 200 m.
(c) moving along -x direction with frequency 10⁶ Hz and wave length 200 m.
(d) moving along y direction with frequency 2π x 10⁶ Hz and wave length 200 m.

Correct Answer:

moving along x direction with frequency 10⁶ Hz and wave length 200 m.

Explanation:

Comparing with the equation of wave,
Ey = E₀ cos (ωt – kx)
ω = 2πf = 2π x 10⁶
Therefore, f = 10⁶ Hz
2π / λ = k = π x 10⁻² m⁻¹, λ = 200 m