XII Physics, Chapter 8 & 15 Electro magnetic waves and communication Chapter8 & 15 electromagnetic waves & communicatio | Page 2

Displacement Current
It is a current which produces in the region in which the electric field and hence the electric flux changes with time .
Displacement current , I D = ε o . dφ E / dt where , φ E is the electric flux .
Ampere-Maxwell Law
where , μ o = Permeability = 4π * 10 -7 V / Am
Maxwell ’ s Equations
This equation is Ampere-Maxwell law .
Electromagnetic Waves
Electromagnetic waves are those waves in which electric and magnetic field vectors changes sinusoidally and are perpendicular to each other as well as at right angles to the direction of propagation of wave .