Electromagnetic Waves

Electromagnetic Waves

* Mwalls segundone wave equation; Plane electromagnetio waves in Valeuum, Conditions on the wave field - properties of electromagnetio waves speed, amplitude, phase, orientation, and waves in matter - polarization - Producing electromagnetic waves - Energy and, momontum In EM wavos Intensity, waves, from localzed: sources - momentum anat radiation prejmuire - Cell-phone reception. Ronection and transdission electromagnetic waves from a nord-cond medłum-vesuum interface for normal ineidence. 

Introduction

• The phenomenon of Faraday's electromagnetic induction concludes that a changing magnetic field at a point with time produces an electric field at that point.

• Maxwell in 1865, pointed out that there is a symmetry in nature (i.e) changing electric field with time at a point produces a magnetic field at that point. It means that a change in one field with time (either electric or magnetic) produces another field.

• This idea led Maxwell to conclude that the variation in electric and magnetic fields perpendicular to each other, produces electromagnetic disturbances in space. These disturbances have the properties of a wave and propagate through space without any material medium. These waves are called electromagnetic waves.

• Maxwell unified the theories of electricity and magnetism by way of deducing four very important equations which combine the experimental observations reported by Gauss, Ampere, and Faraday with his concept of displacement current.