Mar, 2015 electromagnetic radiation is a form of energy that includes radio waves, microwaves, xrays and gamma rays, as well as visible light. Properties of electromagnetic radiation emitted by an. When matter absorbs electromagnetic radiation it undergoes a change in energy. Radiation can be thought of as a traveling transverse wave. Information could be encoded in the frequency content, intensity, or polariza tion of the electromagnetic wave. All electric and magnetic field vectors added together according to vector addition rule. The electromagnetic radiation is characterized based on various properties like frequency, wavelength, time period etc. Basic parameters 1 properties of electromagnetic radiation 3211 wave optics. Conceptually we can talk about electromagnetic radiation. Electromagnetic radiation principles and concepts as applied to. Here we first introduce electromagnetic waves and some of their properties including their structure, energy, and momentum. The source that produce them and methods of their detection are different, but they have the following common properties. These magnetic and electric waves travel perpendicular to each other and have some characteristics like wavelength, amplitude, and frequency. These are bundles of light energy or quantized harmonic waves which travel at the speed of light.
Feb 27, 2016 electromagnetic radiation exhibits properties of a wave or a particle depending on its energy and in some cases its environment. Electromagnetic radiation is a phenomenon that takes the form of selfpropagating energy waves as it travels through space vacuum or matter. Electromagnetic radiation is one of the most important component of remote sensing without which remote sensing is very much difficult. Electromagnetic radiation, is a form of energy emitted by moving charged particles. Wave motion wave motion is the transfer of energy without matter. Then we introduce the idealized blackbody, blackbody radiation,and blackbody radiation function, together with the stefanboltzmann law, plancks law, and wiens displacement law. Jan 12, 2019 you will also understanding electromagnetic radiation properties and different laws that characterize electromagnetic radiation. Introduction knowledge of solar electromagnetic radiation is needed in space vehicle design to establish the thermal balance of the spacecraft. Some other forms of electromagnetic radiation are xrays, microwaves, infrared radiation, am and fm radio waves, and ultraviolet radiation.
Pdf basics of electromagnetic radiation researchgate. Jan 30, 2020 electromagnetic radiation is selfsustaining energy with electric and magnetic field components. The electromagnetic spectrum 1 properties of electromagnetic radiation 3211 the term electromagnetic radiationincludes the entire spectral range from atmospheric radiation at 1023 hz to radio waves at few hz. Some properties of electromagnetic radiation, such as its refraction when it passes from one medium to another figure 10. Because the speed of light is a constant, the wavelength of electromagnetic radiation and. Exploitation of electromagnetic radiation properties for medical diagnostic. The electromagnetic spectrum 8 cesars booklet table 1. This phenomenon is called waveparticle duality, which is essentially the idea that there are two equally correct ways to describe electromagnetic radiation. It can be described using a sinusoidal wave model, where the properties of the radiation depend on the wavelength, frequency, and other parameters of the wave. Electrodynamics is the physics of electromagnetic radiation, and electromagnetism is the physical phenomenon associated with the theory of electrodynamics. Energy transfer by radiation occurs at the speed of light and suffers no attenuation in vacuum. Electric and magnetic fields obey the properties of superposition. Many existing texts cover these phenomena in detail.
We start this chapter with a discussion of electromagnetic waves and the electromagnetic spectrum, with particular emphasis on thermal radiation. When atoms decay, they emit three types of radiation, alpha, beta and gamma. Waves involving springsmasses, strings, and air molecules are things we can apply our intuition to. Electromagnetic waves and their properties boundless physics. Light travels through the vacuum of space unlike sound. There is a spectrum of electromagnetic radiation with variable wavelengths and frequency, which in turn imparts different characteristics. The waves propagate through a vacuum at the speed of light. Swapan kumar haldar, in mineral exploration second edition, 2018. Electromagnetic radiation definition of electromagnetic. However, ionizing electromagnetic radiation has enough energy to eject one or more electrons from the atom. Properties of electromagnetic radiation emitted by an electron diffracted in a single crystal. The alpha and beta radiation consist of actual matter that shoots off the atom, while gamma rays are electromagnetic waves.
The condition in which some electromagnetic radiation photons such as light or xrays are absorbed but some are transmitted through a substance. Electromagnetic radiation, in classical physics, the flow of energy at the universal speed of light through free space or through a material medium in the form of the electric and magnetic fields that make up electromagnetic waves such as radio waves, visible light, and gamma rays. Electromagnetic radiation is characterized by a broad range of wavelengths and frequencies, each associated with a specific intensity or amplitude and quantity of energy. Properties of electromagnetic radiation electromagnetic radiation is the type of energy that encompasses light, heat, and xrays. Laser or optical tweezers is an exciting new technique that allows manipulation of microscopic structures or of.
Mathematically it is equal to the reciprocal of the time period of electromagnetic radiation. Electromagnetic radiation is characterized by its wavelength. Remote sensing is concerned with the measurement of emr returned. The next four chapters discuss various aspects of optics, the science of light. Electromagnetic waves physics definition notes pdf download.
Some properties of electromagnetic radiation, such as its refraction when it passes from one medium to another figure \\pageindex1\, are explained best by describing light as a wave. The radiation of electromagnetic waves can be explained by the behavior of the electromagnetic field produced by timevarying current. The electromagnetic spectrum 3 cesars booklet properties of waves a wave figure 2 is a periodic perturbation from an undisturbed or rest state that is transmitted in space. The oscillations of the electric and magnetic field components are perpendicular to each other and to. Electromagnetic radiation is commonly referred to as light, em, emr, or electromagnetic waves. Electromagnetic radiation properties and laws leave a comment remote sensing by srinivasjbt january 12, 2019 january 12, 2019 in the previous article, we have defined what is remote sensing and what are various constituents or stages of remote sensing. This energy for remote sensing instruments is in the form of electromagnetic radiation emr. If a charged particle interacts with an electromagnetic wave, it experiences a force proportional to the strength of the electric field and thus is forced to change its motion in accordance with the frequency of the electric field wave. Electromagnetic radiation properties and behaviour britannica. For example, sound waves need either a gas, solid, or liquid to pass through in order to be heard. Excitation describes the deposition of enough energy to raise an electron to a higher electron shell without ejection of the electron. For orbits near the earth or other planets, the planetary albedo and emitted radiation also have to be taken into account to achieve thermal balance. Possible effects of electromagnetic fields emf on human health.
All three kinds of radiation are potentially hazardous to living tissue, but some more than others, as will be explained later on. Blackbody is a hypothetical object that is a perfect absorber of electromagnetic radiation at all wavelengths. Visible light, xrays, infrared radiation, and radio waves have different speeds true tf. The interaction between matter and electromagnetic radiation is easiest to understand if we assume that radiation consists of a beam of energetic particles called photons. Energy transfer by waves wave a traveling disturbance properties of waves wavelength frequency velocity amplitude. Thus, emr is sometimes referred to as the far field. Possible effects of electromagnetic fields emf on human.
Interiors of stars for example are like this emission from many objects is roughly of this form. For example, sound waves need either a gas, solid, or liquid to pass through in order to. A thorough appreciation of the behavior and properties of electromagnetic waves is therefore crucial when discussing the performance and reliability of. Most other types of waves must travel through some sort of substance. Electromagnetic radiation can travel through empty space.
Electromagnetic radiation released is related to the temperature of the body. This interactive tutorial explores the relationship between frequency, wavelength, and energy, and enables the visitor. Electromagnetic and particulate radiation radiology key. Electromagnetic radiation wave nature, properties and formula.
Thus, a field due to any particular particle or timevarying electric or magnetic field contributes to the fields present in the same space due to other causes. Electromagnetic radiation radiant energy that exhibits wavelengthlike behavior and travels through space at the speed of light in a vacuum. General properties of all electromagnetic radiation. In this piece of article, we will discuss electromagnetic radiation and its properties. Radiopaque the quality of a structure that is denser and, therefore, absorbs xrays more readily. Pdf exploitation of electromagnetic radiation properties. Pdf basic characteristics of electromagnetic radiation. Electromagnetic radiationlightis a form of energy whose behavior is described by the proper ties of both waves and particles. Electromagnetic radiation exhibits properties of a wave or a particle depending on its energy and in some cases its environment. Stephanboltzmann law says that if this body is a black body, one which perfectly absorbs and emits radiation, the radiation released is equal to the temperature raised to the fourth power. Electromagnetic radiation emr the first requirement for remote sensing is to have an energy source to illuminate the target. Solar radiation is an electromagnetic radiation with wavelength ranging from 0. Additionally, a special property of em radiation is that it displays a fixed speed in vacuum, c, and fixed velocities in.
Electromagnetic energy is the means by which information is transmitted from an object to a sensor. Electromagnetic radiationlightis a form of energy whose behavior is described by the properties of both waves and particles. Basic electromagnetic wave properties java tutorial. Electromagnetic radiation an overview sciencedirect topics. However, at very short wavelengths, it fails to account for certain significant phenomena that occur when the wave interacts with matter. This interactive tutorial explores the relationship between frequency, wavelength, and energy, and enables the visitor to adjust the.
Then based on the wavelength of the electromagnetic spectrum, the energy is grouped into different categories. Examples of astronomical sources emitting in each range of the electromagnetic spectrum. Electromagnetic radiation lightis a form of energy whose behavior is described by the proper ties of both waves and particles. The electric e g and magnetic h g fields oscillate. Electromagnetic radiation exhibits wavelike properties such as reflection, refraction, diffraction, and interference, but also exhibits particlelike properties in that its energy occurs in. Electromagnetic radiation is associated with those em waves that are free to propagate themselves radiate without the continuing influence of the moving charges that produced them, because they have achieved sufficient distance from those charges. Chapter 2 the properties of electromagnetic radiation radio jove. Electromagnetic induction waves interference of waves. Possible effects of electromagnetic fields emf on human health 6 executive summary the scientific committee on toxicity, ecotoxicity and the environment cstee presented an opinion on possible effects of electromagnetic fields emf, radio frequency fields rf and microwave radiation on human health in 2001. Electromagnetic radiation properties and laws just btech. This is measured in watts per metre square wm 2 using a pyranometer or a pyheliometer. Both are vector fields and both are perpendicular to each other this means that the angle between the electric field and magnetic field is 90 degrees. Wave properties of electromagnetic radiation two options are available for analytical utility when an analyte interacts with a beam of electromagnetic radiation in an instrument 1.
Chapter maxwells equations and electromagnetic waves. Radiation heat transfer radiation differs from conduction and convection heat t transfer mechanisms, in the sense that it does not require the presence of a material medium to occur. As it travels through space it behaves like a wave, and has an oscillating electric field component and an oscillating magnetic field. The variation of electric and magnetic fields, perpendicular to each other, producing electromagnetic disturbance in space at right angles to each other, which have properties of waves and propagate through free space without any materialistic medium is called electromagnetic. We can monitor the changes that occur in the radiation after the interaction, or in this case, wave properties of the electromagnetic radiation is useful. The electrical characteristics of the electromagnetic field are presented as the characteristic impedance of the free space. Every form of electromagnetic radiation, including visible light. Em radiation or electromagnetic radiation is an energy form that is present all around us and takes various forms like microwaves, radio waves, gamma rays, xrays, etc. Climatically relevant are mainly the following wavelength ranges. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Electromagnetic radiation properties and behaviour. But well now switch gears and talk about electromagnetic waves. Type of radiation temperature typical sources gammarays 108 k matter falling into black holes xrays 106108 k gas in clusters of galaxies supernova remnants stellar coronae.