Question

A plane electromagnetic waves of frequency 25 mega hertz travel in free space along x direction. At a particular point in the space and time E= 6.3j V/m.what is B vector of that point

Answer 1

• Solution:
The magnitude of B is,
B = E/c
= 6.3 v/m / 3 * 10^-8 m/s
=2.1 * 10^-8 T.
To find the direction, we note that E is along y-direction and the wave propagates along x-axis.
Therefore, B should be in a direction perpendicular to both x-axes and y-axes. Using vector
algebra, E × B should be along x-direction. So B should be along z-direction. Thus, B = 2.1 × 10^-8 T.