Electromagnetic Waves Test - 4

A time varying magnetic field is a source of changing electric field. And a time varying electric field is a source of changing magnetic field. These variations in electric field and magnetic fields occur in mutually perpendicular directions and have wave like properties. Maxwell was thus led to the idea that a wave of electric and magnetic fields both varying with  space and time should exist, one providing the source of another. Such a wave is called electromagnetic wave.

Maxwell showed that Ampere's circuital law is logically inconsistent. He considered a parallel plate capacitor being charged be a battery. He showed inconsistency of the law in the regions outside the plates of capacitor and just between the plates. To resolve this inconsistency displacement current was introduced by Maxwell.

This charge produces an oscillating electric field in its neighbourhood. This field in turn, produces an oscillating magnetic field in its neighbourhood. The process continues as both the fields acts as source of each other. Hence, an em wave originates from the oscillating charge.
Note: The frequency of em wave is equal to frequency of oscillating charge.

Wave vector, k is the spatial angular frequency of the wave, describing how many oscillations it completes per unit of space, and related to the wavelength by the equation k=2π/λ

Since both electric and magnetic fields oscillates perpendicular to direction of propagation of em-wave, it is transverse in nature.