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- https://phys.libretexts.org/Courses/Bowdoin_College/Phys1140%3A_Introductory_Physics_II%3A_Part_1/07%3A_Electromagnetic_Waves/7.03%3A_Plane_Electromagnetic_WavesMechanical waves travel through a medium such as a string, water, or air. Perhaps the most significant prediction of Maxwell’s equations is the existence of combined electric and magnetic (or electrom...Mechanical waves travel through a medium such as a string, water, or air. Perhaps the most significant prediction of Maxwell’s equations is the existence of combined electric and magnetic (or electromagnetic) fields that propagate through space as electromagnetic waves. Because Maxwell’s equations hold in free space, the predicted electromagnetic waves, unlike mechanical waves, do not require a medium for their propagation.
- https://phys.libretexts.org/Bookshelves/Electricity_and_Magnetism/Electromagnetics_and_Applications_(Staelin)/10%3A_Antennas_and_Radiation/10.03%3A_Antenna_gain_effective_area_and_circuit_propertiesThis page covers the fundamentals of antenna directivity, gain, and impedance, focusing on short dipole antennas. It defines key relationships between gain, radiation resistance, and the effective are...This page covers the fundamentals of antenna directivity, gain, and impedance, focusing on short dipole antennas. It defines key relationships between gain, radiation resistance, and the effective area, employing Thevenin equivalents to analyze antenna circuits. The reciprocity principle is emphasized, detailing how transmitted power impacts received power across distances.
- https://phys.libretexts.org/Bookshelves/College_Physics/College_Physics_1e_(OpenStax)/24%3A_Electromagnetic_Waves/24.01%3A_Maxwells_Equations-_Electromagnetic_Waves_Predicted_and_ObservedElectromagnetic waves consist of oscillating electric and magnetic fields and propagate at the speed of light c. They were predicted by Maxwell, who also showed that \[c = \frac{1}{\sqrt{\mu_{0} \...Electromagnetic waves consist of oscillating electric and magnetic fields and propagate at the speed of light c. They were predicted by Maxwell, who also showed that c=1√μ0ϵ0, where mu0 is the permeability of free space and ϵ0 is the permitivity of free space. Maxwell’s prediction of electromagnetic waves resulted from his formulation of a complete and symmetric theory of electricity and magnetism, known as Maxwell’s equations.
- https://phys.libretexts.org/Courses/Georgia_State_University/GSU-TM-Physics_II_(2212)/08%3A_Electromagnetic_Waves/8.02%3A_Electromagnetic_WavesWe see that the magnetic field wave function has the same frequency and wavelength as the electric field wave function, and since the ratio Tλ is just the inverse of the speed of t...We see that the magnetic field wave function has the same frequency and wavelength as the electric field wave function, and since the ratio Tλ is just the inverse of the speed of the wave c, which means that the amplitudes of the electric and magnetic parts of the wave are related by:
- https://phys.libretexts.org/Courses/Bowdoin_College/Phys1140%3A_Introductory_Physics_II%3A_Part_1/07%3A_Electromagnetic_Waves/7.04%3A_Energy_Carried_by_Electromagnetic_WavesElectromagnetic waves bring energy into a system by virtue of their electric and magnetic fields. These fields can exert forces and move charges in the system and, thus, do work on them. However, ther...Electromagnetic waves bring energy into a system by virtue of their electric and magnetic fields. These fields can exert forces and move charges in the system and, thus, do work on them. However, there is energy in an electromagnetic wave itself, whether it is absorbed or not. Once created, the fields carry energy away from a source. If some energy is later absorbed, the field strengths are diminished and anything left travels on.
- https://phys.libretexts.org/Bookshelves/Waves_and_Acoustics/The_Physics_of_Waves_(Goergi)/12%3A_Polarization/12.02%3A_Electromagnetic_WavesThe components, ψ1 and ψ2 go into the the two-dimensional vector, (12.3), that describes the polarization state of the electromagnetic wave, just as it describes the polarization s...The components, ψ1 and ψ2 go into the the two-dimensional vector, (12.3), that describes the polarization state of the electromagnetic wave, just as it describes the polarization state of the string. This is related to the fact that the circularly polarized states carry the maximum angular momentum possible, which in turn is related to the quantum mechanical property of the spin of the photon.
- https://phys.libretexts.org/Bookshelves/Electricity_and_Magnetism/Electromagnetics_and_Applications_(Staelin)/12%3A_Optical_Communications/12.03%3A_LasersThis page explains the functioning of lasers, including their reliance on quantum processes for coherent light generation and the importance of population inversion. It addresses the efficiency of thr...This page explains the functioning of lasers, including their reliance on quantum processes for coherent light generation and the importance of population inversion. It addresses the efficiency of three- and four-level lasers, challenges in building high-energy lasers, and concepts such as laser oscillators and diodes. The text also covers the impact of resonant frequencies, line broadening effects, and molecular collisions on laser operations.
- https://phys.libretexts.org/Bookshelves/Electricity_and_Magnetism/Electricity_and_Magnetism_(Tatum)/15%3A_Maxwell's_Equations/15.09%3A_Electromagnetic_WavesMaxwell predicted the existence of electromagnetic waves, and these were generated experimentally by Hertz shortly afterwards. In addition, the predicted speed of the waves was \(3 \times 10^{8}\, m ...Maxwell predicted the existence of electromagnetic waves, and these were generated experimentally by Hertz shortly afterwards. In addition, the predicted speed of the waves was 3×108ms−1, the same as the measured speed of light, showing that light is an electromagnetic wave.
- https://phys.libretexts.org/Courses/Kettering_University/Electricity_and_Magnetism_with_Applications_to_Amateur_Radio_and_Wireless_Technology/20%3A_Maxwell's_Equations/20.06%3A_Plane_Electromagnetic_WavesMechanical waves travel through a medium such as a string, water, or air. Perhaps the most significant prediction of Maxwell’s equations is the existence of combined electric and magnetic (or electrom...Mechanical waves travel through a medium such as a string, water, or air. Perhaps the most significant prediction of Maxwell’s equations is the existence of combined electric and magnetic (or electromagnetic) fields that propagate through space as electromagnetic waves. Because Maxwell’s equations hold in free space, the predicted electromagnetic waves, unlike mechanical waves, do not require a medium for their propagation.
- https://phys.libretexts.org/Courses/Kettering_University/Electricity_and_Magnetism_with_Applications_to_Amateur_Radio_and_Wireless_Technology/22%3A_Generation_and_Detection_of_Electromagnetic_Waves/22.02%3A_Production_of_Electromagnetic_Waves_-_The_AntennaElectromagnetic waves are created by oscillating charges (which radiate whenever accelerated) and have the same frequency as the oscillation. Since the electric and magnetic fields in most electromagn...Electromagnetic waves are created by oscillating charges (which radiate whenever accelerated) and have the same frequency as the oscillation. Since the electric and magnetic fields in most electromagnetic waves are perpendicular to the direction in which the wave moves, it is ordinarily a transverse wave. The strengths of the electric and magnetic parts of the wave are related by EB=c, which implies that the magnetic field B is very weak relative to the electric field E.
- https://phys.libretexts.org/Bookshelves/Electricity_and_Magnetism/Electromagnetics_and_Applications_(Staelin)/10%3A_Antennas_and_Radiation/10.02%3A_Short_dipole_antennasThis page covers the radiation emitted by Hertzian dipoles, including the derivation of electromagnetic fields using Maxwell’s equations and the Biot-Savart law. It emphasizes the behavior of far-fiel...This page covers the radiation emitted by Hertzian dipoles, including the derivation of electromagnetic fields using Maxwell’s equations and the Biot-Savart law. It emphasizes the behavior of far-field and near-field radiation, detailing the donut-shaped radiation pattern and the conversion of electromagnetic waves to circuit voltages by antennas. The analysis includes θ-polarized plane waves, focusing on intensity and total power radiated, with dependencies on antenna efficiency and wavelength.
