The oscillating magnetic field in a plane electromagnetic wave is given by

B

_{y}= ( 8 x 10^{-6}) sin ( 2 x 10^{11 }t + 300πx ) Τ1)Calculate the wavelength of the electromagnetic wave

2)The direction of electric field and direction of propagation of the

electromagnetic wave?

Given that

B* _{y}* = (8 × 10

^{– 6}) sin (2 × 10

^{11}

*t*+ 300

*π r*) T .....(1)

We know that

B_{y} = B_{0} sin (W*t* – 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)

B_{0 }= 8 × 10^{– 6} T

W = 2 × 10^{11 }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.

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