Electromagnetic Waves
Subject and UNIT: Electromagnetic Theory: Unit V: Electromagnetic Waves
• By the means of electromagnetic (EM) waves, an energy can be transported from transmitter to receiver. The energy stored in an electric field and magnetic field is transmitted at a certain rate of energy flow which can be calculated with the help of Poynting theorem.
Subject and UNIT: Electromagnetic Theory: Unit V: Electromagnetic Waves
• A practical or good conductor is the material which has very high conductivity. In general, the conductivity is of the order of 107 Ʊ/m in the good conductors like copper, aluminium etc.
Electromagnetic Waves
Subject and UNIT: Electromagnetic Theory: Unit V: Electromagnetic Waves
• Practically all the dielectric materials exhibit some conductivity (σ ≠ 0). So during analysis of the uniform plane waves through dielectric with some amount of conductivity, we cannot neglect o by assuming it to be zero.
Electromagnetic Waves
Subject and UNIT: Electromagnetic Theory: Unit V: Electromagnetic Waves
• Consider that the uniform plane wave is propagating through a perfect dielectric. If the medium is perfect dielectric, then its properties are given by, σ = 0, μ = μr μ0 and ε = εr ε0. For the perfect dielectric as conductivity is zero (i.e. σ = 0), the medium is also called lossless medium.
Electromagnetic Waves
Subject and UNIT: Electromagnetic Theory: Unit V: Electromagnetic Waves
• An electromagnetic wave in a medium can be completely defined if intrinsic impedance (ɳ) and propagation constant (ɤ) of a medium is known. Thus it is necessary to derive the expressions for n and y interms of the properties of a medium such as permeability (µ) permittivity (Ɛ), conductivity (σ) etc.
Electromagnetic Waves
Subject and UNIT: Electromagnetic Theory: Unit V: Electromagnetic Waves
• Consider an electromagnetic wave propagating through the free space. For free space, σ = 0. Consider that the electric field in the wave is in x-direction only while the magnetic field is in y-direction only.
using Maxwell's equations | Electromagnetic Waves
Subject and UNIT: Electromagnetic Theory: Unit V: Electromagnetic Waves
• In general the wave equations can be obtained by relating the space and time variations of the electric and magnetic fields, using the Maxwell's equations.
Electromagnetic Waves
Subject and UNIT: Electromagnetic Theory: Unit V: Electromagnetic Waves
• The Maxwell's equations for time varying fields form the basics for the explanation of the electromagnetic wave propagation. The existance of the electromagnetic waves was first stated by Prof. Heinrich Hertz.
Electromagnetic Theory
Subject and UNIT: Electromagnetic Theory: Unit V: Electromagnetic Waves
Electromagnetic Theory: Unit V: Electromagnetic Waves : Syllabus, Contents
Time Varying Fields and Maxwells Equations | Electromagnetic Theory
Subject and UNIT: Electromagnetic Theory: Unit IV: Time Varying Fields and Maxwells Equations
Electromagnetic Theory: Unit IV: Time Varying Fields and Maxwell's Equations :
Time Varying Fields and Maxwells Equations | Electromagnetic Theory
Subject and UNIT: Electromagnetic Theory: Unit IV: Time Varying Fields and Maxwells Equations
Electromagnetic Theory: Unit IV: Time Varying Fields and Maxwell's Equations : Two Marks Questions with Answers
Time Varying Fields and Maxwells Equations
Subject and UNIT: Electromagnetic Theory: Unit IV: Time Varying Fields and Maxwells Equations
1. Transformers 2. Magnetic Brake 3. Induction Heating 4. Magnetic Levitation 5. Electromagnetic Propulsion of Ships and Submarines 6. Electromagnetic Launcher (EML) 7. Electromagnetic Forming 8. Eddy Current Testing of Materials 9. Magnetohydrodynamic (MHD) Generator