7 Examples of Electromagnetic Waves and Applications Discussed
Examples of electromagnetic waves are; gamma rays in sterilization, X-rays in bone examination, ultraviolet radiation for dermatological treatment, visible light for photography, infrared rays for heat sensing, microwaves in domestic systems, and radio waves in communication networks.
The discussion in this article simultaneous covers examples and uses of electromagnetic waves, as follows;
1). Gamma Rays in Sterilization Systems (as one of the Examples of Electromagnetic Waves)
Alpha and beta electron beams, as well as x-rays and gamma rays can all be used for sterilization of materials used for medical and cosmetic purposes, among others [1].
Gamma radiation is used in sterilization because it is highly effective for eliminating persistent microorganisms [4].
The use of gamma rays for sterilization is common with tissue allografts and medical devices.
It is effective because of its high energy exposition that enables it penetrate materials easily, killing microbes through the breakdown of their DNA structures.
As an electromagnetic wave, gamma radiation comes first in the EM spectrum when arranged in descending order of frequency, or ascending order of wavelength. A high frequency implies that gamma rays are highly energetic, and can cause the gain or loss of electrons from atoms with which they collide. They are therefore among the EM waves referred to as ionizing waves [5].
2). X-Rays in Bone Examination
X-rays are used for examining bones because of their ability to penetrate through tissues of the human body, and produce images of internal bone structures and conditions.
An X-ray examination of bones (or X-ray imaging) is simply the process whereby a beam of high-frequency, x-ray electromagnetic waves are projected unto a part of the body which it penetrates to illuminate bones that are captured on a screen [6].
Doctors use X-rays to understand bone structure, conditions and configuration, especially in order to diagnose related medical issues like fractures, dislocations, deformities and osteoporosis, among others.
Aside plain radiography for bone examination, X-rays can also be used for mammography, fluoroscopy, angiography and computed tomography, which are concerned with examination of the breasts, organ-functions, and blood vessels.
The use of X-rays for viewing internal body components and conditions is possible because these electromagnetic waves vibrate with high frequency, like gamma rays. They are also ionizing, and may alter genetic material on extended exposure.
3). Ultraviolet Radiation for Dermatological Treatment (as one of the Examples of Electromagnetic Waves)
Ultraviolet radiation is used in dermatology to treat certain skin conditions such as atopic dermatitis, eczema, vitiligo, psoriasis, mycosis fungoides, as well as symptoms like inflammation and itching [8].
The use of ultraviolet radiation in dermatology is called ultraviolet radiation skin treatment, or phototherapy. It basically involves exposing the skin to ultraviolet light under controlled conditions [9].
UV light can also be used to treat skin cancer, including Psoralen-UVA (PUVA) and Narrow-band ultraviolet B (NB-UVB) [3]. Often, phototherapy is combined with medication to increase the sensitivity of the skin to UV rays.
4). Visible Light for Photography
Visible light can be used for photography, to illuminate objects and enable a light-sensitive camera capture clear images.
The visible light which illuminates objects in photography also interacts with the lens and filters of the camera that is used for image-capturing.
Visible light is important in photography as it determines the quality of output, in terms of parameters like clarity, tone, contrast and mood of photographs.
In terms of frequency, visible lights is part of the low-frequency category of electromagnetic waves, and is non-ionizing; meaning that long-term exposure does not pose any significant health risks.
5). Infrared Rays for Heat Sensing (as one of the Examples of Electromagnetic Waves)
Infrared rays are used to detect thermal energy or heat that is emanating from objects or bodies in a given area. This is possible with heat sensors; which are designed to sense electromagnetic waves vibrating in the frequency range of infrared radiation (which is between visible light and microwaves).
The use of infrared heat sensors to detect heat in a surrounding is possible because all objects emit infrared radiation as heat, which can be used to estimate the temperatures of these objects [7].
6). Microwaves in Domestic Heating Systems
Microwaves are used for heating by radiant energy-transfer, whereby significant amounts of electromagnetic radiation are directed toward a substrate, which absorbs the radiation and heats up.
The principle of microwave heating for domestic purposes is based on multiple reflection of microwave rays off the surfaces of an enclosure, which is commonly called the microwave oven.
Reflection makes it possible for a relatively small amount of microwave radiation to be used, thereby playing the role of energy conservation in microwave heating systems. The target may also be rotated for maximum coverage during the heating process.
A common domestic use of microwave heating is in food preparation or preservation [10]. Water heating can also be achieved using microwaves.
7). Radio Waves in Communication Networks (as one of the Examples of Electromagnetic Waves)
One of the most common uses of radio waves is to communicate and transfer information in radio, television, cellular and IoT networks [2].
The suitability of radio waves for this purpose can be attributed to some of its characteristics, which include long wavelength and non-ionizing effect.
Types of radio waves used in communication are High-Frequency (HF), Very-High Frequency (VHF), and Ultrahigh Frequency (UHF) radio waves (where the latter two can be considered subtypes under High-Frequency waves).
Conclusion
Examples of electromagnetic waves are;
1. Gamma Rays in Sterilization Systems
2. X-Rays in Bone Examination
3. Ultraviolet Radiation for Dermatological Treatment
4. Visible Light for Photography
5. Infrared Rays for Heat Sensing
6. Microwaves in Domestic Heating
7. Radio Waves in Communication
References
1). Aquino, K. A. S. (2012). "Sterilization by Gamma Irradiation." Gamma Radiation. Available at: https://doi.org/10.5772/34901. (Accessed 31 March 2023).
2). Chapagain, N. P. (2014). "Radio wave communication system and mobile phone." Available at: https://www.researchgate.net/publication/322602642_Radio_wave_communication_system_and_mobile_phone. (Accessed 31 March 2023).
3). Darukarnphut, P.; Rattanakaemakorn, P.; Rajatanavin, N. (2017). "A Retrospective Study on the Risk of Non-Melanoma Skin Cancer in PUVA and Narrowband UVB Treated Patients." Available at: https://doi.org/10.26502/acbr.50170014. (Accessed 31 March 2023).
4). Harrell, C. R.; Djonov, V.; Fellabaum, C.; Volarevic, V. (2018). "Risks of Using Sterilization by Gamma Radiation: The Other Side of the Coin." Int J Med Sci. 2018 Jan 18;15(3):274-279. Available at: https://doi.org/10.7150/ijms.22644. (Accessed 31 March 2023).
5). Kharisov, B. I.; Kharissova, O. V. (2013). "Main Ionizing Radiation Types and Their Interaction with Matter." Available at: https://www.researchgate.net/publication/262451167_Main_Ionizing_Radiation_Types_and_Their_Interaction_with_Matter. (Accessed 31 March 2023).
6). Larkin, A.; Sheahan, N.; O'Connor, U.; Gray, L.; Dowling, A.; Vano, E.; Torbica, P.; Salat, D.; Schreiner, A.; Neofotistou, V.; Malone, J. F. (2008). "QA/acceptance testing of DEXA X-ray systems used in bone mineral densitometry." Radiat Prot Dosimetry. 2008;129(1-3):279-83. Available at: https://doi.org/10.1093/rpd/ncn086. (Accessed 1 April 2023).
7). Lucas, J. (2019). "What Is Infrared?" Available at: https://www.livescience.com/50260-infrared-radiation.html. (Accessed 31 March 2023).
8). Situm, M.; Bulat, V.; Majcen, K.; Dzapo, A.; Jezovita, J. (2014). "Benefits of controlled ultraviolet radiation in the treatment of dermatological diseases." Coll Antropol. 2014. Available at: https://www.semanticscholar.org/paper/Benefits-of-controlled-ultraviolet-radiation-in-the-Šitum-Bulat/dc2e2f360bf6392ba7fd974171e18a260da1e177. (Accessed 31 March 2023).
9). Tee-Melegrito, R. A. (2021). "What to know about UV light therapy and atopic dermatitis." Available at: https://www.medicalnewstoday.com/articles/atopic-dermatitis-ultraviolet-light-therapy. (Accessed 31 March 2023).
10). Woodford, C. (2021). "Microwave ovens." Available at: https://www.explainthatstuff.com/microwaveovens.html. (Accessed 31 March 2023).
