Electromagnetic Waves

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Introduction to electromagnetic waves, wave properties, propagation, diffraction, polarization, reflection and refraction, ionosphere propagation, waveguides.

Quote: "In physics, electromagnetic radiation (EMR) consists of waves of the electromagnetic (EM) field, which propagate through space and carry momentum and electromagnetic radiant energy."
Quote: "Types of EMR include radio waves, microwaves, infrared, (visible) light, ultraviolet, X-rays, and gamma rays, all of which are part of the electromagnetic spectrum."
Quote: "Electromagnetic waves travel at the speed of light, commonly denoted c."
Quote: "Electromagnetic waves consist of synchronized oscillations of electric and magnetic fields."
Quote: "The position of an electromagnetic wave within the electromagnetic spectrum can be characterized by either its frequency of oscillation or its wavelength."
Quote: "Electromagnetic waves of different frequency are called by different names since they have different sources and effects on matter."
Quote: "Electromagnetic waves are emitted by electrically charged particles undergoing acceleration."
Quote: "EM waves carry energy, momentum, and angular momentum away from their source particle and can impart those quantities to matter with which they interact."
Quote: "EMR is sometimes referred to as the far field. In this language, the near field refers to EM fields near the charges and current that directly produced them."
Quote: "EMR consists of photons, uncharged elementary particles with zero rest mass which are the quanta of the electromagnetic field, responsible for all electromagnetic interactions."
Quote: "Quantum electrodynamics is the theory of how EMR interacts with matter on an atomic level."
Quote: "Quantum effects provide additional sources of EMR, such as the transition of electrons to lower energy levels in an atom and black-body radiation."
Quote: "The energy of an individual photon is quantized and is greater for photons of higher frequency."
Quote: "This relationship is given by Planck's equation E = hf, where E is the energy per photon, f is the frequency of the photon, and h is Planck's constant."
Quote: "EMR of visible or lower frequencies... is called non-ionizing radiation, because its photons do not individually have enough energy to ionize atoms or molecules, or break chemical bonds."
Quote: "The effects of these radiations on chemical systems and living tissue are caused primarily by heating effects from the combined energy transfer of many photons."
Quote: "High frequency ultraviolet, X-rays and gamma rays are called ionizing radiation since individual photons of such high frequency have enough energy to ionize molecules or break chemical bonds."
Quote: "These radiations have the ability to cause chemical reactions and damage living cells beyond that resulting from simple heating."
Quote: "The effects of EMR upon chemical compounds and biological organisms depend both upon the radiation's power and its frequency."
Quote: "These radiations can be a health hazard."