Electromagnetic spectrum radiation types

Fig. 1.5 The electromagnetic spectrum radiation type, scale of wavelength, frequency, and...

Figure 6.1 Electromagnetic spectrum. Each type of radiation is spread over a specific range of wavelengths (and frequencies). Visible light ranges from 400 nm (violet) to 700 nm (red).

A university student recently had a busy day. Each of the student s activities on that day (reading, having a dental x-ray, making popcorn in a microwave oven, and getting a suntan) involved radiation from a different part of the electromagnetic spectrum. Complete the following table and match each type of radiation to the appropriate event ... 

The increase in energy in a molecule that occurs when radiation is absorbed can be accommodated in the three ways already described. The range of energies involved is characteristic of each type of change and is associated with a well-defined region of the electromagnetic spectrum (Figure 2.3). 

Different types of electromagnetic radiation make up the electromagnetic spectrum. Visible light - the radiation that our eyes can detect - makes up only a small part of the electromagnetic spectrum. 

CONTINUUM THERMAL RADIATION Radiation which involves the transfer of heat by electromagnetic waves, confined to the relatively narrow window of the electromagnetic spectrum (i.e. visible light around 400 nm to infrared light around 1000 nm). The hot particles in and above hrework flames contribute to this type of radiation. 

The electromagnetic spectrum can be divided into distinct ranges from low-energy long-wave radiation to high-energy short-wave X rays and beyond (Fig. 3). From a spectroscopic point of view, the basis of these different ranges is the nature or type... 

Fig. 1.8 The electromagnetic spectrum, showing the wavelengths and frequencies of different types of radiation. Note the logarithmic scales, with each division representing a factor of ten different from the next one. The spectrum extends Indefinitely in either direction. Except for visible light (determined by the sensitivity of the human eye)the bowdaries between different types of radiation are not precise.

The effect of various types of radiation on polymers has been studied extensively however, if we are interested mainly in effects which occur in a terrestrial atmosphere (i.e., conventional weathering ) we must restrict our attention to a rather narrow band of electromagnetic spectrum. In fact, we must concern ourselves primarily with the energy emitted by the sun and transmitted by the earth s atmosphere. 

So far as the classification of the type of spectroscopy performed is concerned, the characterisation of the dynamical motions of the nuclei and electrons within a molecule is more important than the region of the electromagnetic spectrum in which the corresponding transitions occur. However, before we come to this in more detail, a brief discussion of the nature of electromagnetic radiation is necessary. This is actually a huge subject which, if tackled properly, takes us deeply into the details of classical and semiclassical electromagnetism, and even further into quantum electrodynamics. The basic foundations of the subject are Maxwell s equations, which we describe in appendix 1.1. We will make use of the results of these equations in the next section, referring the reader to the appendix if more detail is required. 

Different types of electromagnetic radiation make up the electromagnetic spectrum. 

As with UV-vis spectroscopy, IR and NMR spectroscopy are based on the interaction of electromagnetic radiation with molecules, whereas MS is different in that it relies on high-energy particles (electrons or ions) to break up the molecules. The relationship between the various types of spectroscopy and the electromagnetic spectrum is shown in Table 28.1. 

Figure 1.4 The electromagnetic spectrum showing wavelengths of different types of radiation. (From Universe, 6th ed., by Roger A. Freedman, and William J. Kaufmann. Ill, 1985, 1988, 1991, 1994, 1999, 2002 by W. H. Freeman and Company. Used with permission. )...

Name some types of radiation that compose the electromagnetic spectrum. 

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