A plane Electromagnetic Waves travelling along the X-direction has a wavelength of 3 mm. The variation in the electric field occurs in the Y-direction with an amplitude 66 Vm-1. The equations for the electric and magnetic fields as a function of x and t are respectively
Answer & explanation
Correct answer: option 4
The equation of electric field occurring in Y- direction
$E_y = 66\, cos 2\pi × 10^{11} ( t - \frac{x}{c})$
Therefore, for the magnetic field in Z-direction
$B_z = \frac{E_y}{c}$
$=(\frac{66}{3×10^8}) cos 2 \pi × 10^{11} ( t - \frac{x}{c})$
$=22 × 10^{-8} cos 2\pi × 10^{11} ( t - \frac{x}{c})$
$=22 × 10^{-7} cos 2\pi × 10^{11} ( t - \frac{x}{c})$