A plane electromagnetic wave of wavelength 3.0m travels infree space in the +x direction. Its electric field vector E has anamplitude of 300 V/, and is directed along the +y direciton. a) waht is the frequency of the wave? b) what are the direction and amplitude of the associatedmagnetic field B? c) If E=^yE0sin(kx-wt), what are the magnitudes of k andw? A plane electromagnetic wave of wavelength 3.0m travels infree space in the +x direction. Its electric field vector E has anamplitude of 300 V/, and is directed along the +y direciton. a) waht is the frequency of the wave? b) what are the direction and amplitude of the associatedmagnetic field B? c) If E=^yE0sin(kx-wt), what are the magnitudes of k andw?
Explanation / Answer
Wavelength = 3 m frequency f = c / =( 3 * 10 ^ 8 m / s ) / 3 m = 10 ^ 8 Hz (b). Amplitude of magnetic field B = E / c = ( 300 V / m ) / ( 3 * 10 ^ 8 m / s ) =10 ^ -6 T magnetic field is along + Z-direction ( c ) . Magnitude of k = 2 / = 2.094 m ^ -1 magnitude of w = 2f = 6.28* 10 ^ 8 rad / s