The oscillating magnetic field in a plane electromagnetic wave is given by
By= ( 8 x 10-6) sin ( 2 x 1011 t + 300πx ) Τ
1)Calculate the wavelength of the electromagnetic wave
2)The direction of electric field and direction of propagation of the
electromagnetic wave?
Given that
By = (8 × 10– 6) sin (2 × 1011 t + 300 π r) T .....(1)
We know that
By = B0 sin (Wt – K x) .....(2)
It shows that variation of magnetic field is along y – axis. And wave is propagating along (+) ve x direction.
Compare equation (1) and (2)
B0 = 8 × 10– 6 T
W = 2 × 1011 rad/s
K = – 300 π m–1
(–)ve sign show that give wave is propagating along (–)ve x–axis.
(1)
(2) We know that
Hence the direction of electric field along z–axis
And direction of propagation of the electromagnetic wave is negative x direction.