Production Of Electromagnetic Waves

-the electric and magnetic fields at any point are perpendicular to each other and to direction of motion;

-fields alternate in direction from point to point;

-the electric and magnetic fields are “in phase”.

EM waves are produced by accelerating electric charges.

Speed of EM Waves

00

1

v

Electromagnetic Spectrum

Example

Calculate the wavelength:

(a)Of a 60-Hz EM wave;

(b)Of a 93.3 MHz FM radio wave;

(c)Of a beam of visible red light from a laser at frequency 4.74x1014 Hz.