The electric field on an electromagnetic wave in free space is given by
`E=10 cos (10^7t+kx) hatj V//m`,
Where t and x are in seconds and metres respectively. It can be inferred that
(1) the wavelength `lambda` is `188.4m`.
(2) the wave number k is `0.33rad//m`
(3) the wave amplitude is `10V//m`
(4) the wave is propagating along +x direction.
which one of the following pairs of statement is correct?

Options

A. (iii) and (iv)
B. (i) and (ii)
C. (ii) and (iii)
D. (i) and (iii)

Answer

D

Explanation

Both electric and magnetic field vectors are parallel to each other perpendicular to the direction of propagation of wave.