Essay On Electromagnetic Radiation

The electromagnetic spectrum is all around us and serves many beneficial and lifesaving purposes every day. There is no escaping it, because much of the spectrum cannot be seen. We can tell it has taken place by getting a tan or sunburn or by the fact that our plants and flowers thrive and grow. This includes x-rays, gamma rays, visible, ultraviolet, infrared light, radio waves and microwaves. While it has many useful purposes, it can also have many negative consequences due to overexposure, some that can even be very fatal. Within this paper we will take a deeper look at what electromagnetic radiation is, how it is produced and detected, as well as the useful purposes and what we can do to protect ourselves from overexposure.

Electromagnetic radiation is the energy result that occurs when electrically charged particles travel through matter or empty space. These particles interact at a ninety degree angle with magnetic fields. The electric field is in a vertical plane, while the magnetic field is in a horizontal plane. This relationship between the electric and magnetic fields causes a disturbance, and thus a combined moving wave, to be formed from the

accelerated charged particles (refer to Figure 1). This wave is called an electromagnetic wave or, more specifically, a transverse wave. These waves are measured by their length or frequency. Wavelengths are measured in meters corresponding to the distances between crests (high points) or troughs (low points) are usually expressed by the Greek symbol λ. Frequency is the number of cycles a wave goes through per second and is expressed in Hertz. A radiation's frequency is inversely related to its wavelength. The shorter a wave length is the greater the frequency and the higher the energy level present.

Figure 1

These varying wavelengths are organized into the Electromagnetic Spectrum. The shortest wavelengths are placed farthest left (or bottom) on the spectrum and display the highest frequencies. As one moves further towards the right (or top), the wavelengths increase while the frequencies decrease respectively (refer to Figures 2 and 3). The speed that electromagnetic waves travel is constant and equal to the speed of light. Thus the speed of a wave equals to the frequency times the wavelength. This statement is expressed by the equation: λν = c where λ stands for wavelength, ν stands for frequency, and c stands for the speed of light in place of 3.0 x 108 m/s.

Figure 2

Figure 3

Each particular frequency of light has a specific energy that is associated with it. This is expressed through the use of the equation: E= hf, where E stands for the energy of the light, h stands for Planck's constant (6.62607004 × 10-34 m2 kg / s), and f stands for the frequency of the light. The light with the highest energy will be the one with the highest frequency and the shortest wavelength.

Electromagnetic radiation is produced when atoms are heated to a very high state.

Heating the atom causes it to absorb energy. The atom does not like being in this high energy state. In order for the atom to settle back into its original state, it gives off an electromagnetic wave. The wave can take the form of heat, light, ultraviolet, or a number of other electromagnetic wave types. Just about everything gives off electromagnetic radiation. One example, is a neon sign. By putting electricity through the neon tubes, it will excite and add energy to the neon atoms causing them to absorb the energy, putting them in a high energy state. Light bulbs work in the same manner, producing radiation waves. Ultraviolet rays are produced from the sun. Infrared rays can be produced by electronic devices and

household

appliances. X-rays can be produced by X-ray machines. Gamma rays are emitted during nuclear explosions.

Electromagnetic radiation can be detected in many different ways. Gamma rays are detected by using a Geiger-Muller tube. X-rays can be detected with photographic film. Ultraviolet (UV) can be detected with photographic film or observation of skin (sun tans and skin cancer). Visible light can be detected with the eyes, photographic film, and an LDR. Infra-red (IR) can be detected on skin, a blackened thermometer, or a thermistor. Microwaves are detected by aerial short wave radio sets, or a simple satellite dish. Radio and Television waves are detected with aerial, with a TV set, or a radio set (they cannot be heard).

Many of the wavelengths from the electromagnetic spectrum are not only useful, but are beneficial for life on earth. Most of us use radio waves every day. These include using your microwave to warm something up or turning on the television to watch your local news or favorite show. Ultraviolet wavelengths are so important because they transmit heat and give us light to see. The sunlight is also critical for all life on earth, including plants and trees. It is also useful for getting that nice summer tan (when used with a reliable sun tan lotion for protection). The electromagnetic spectrum is also used in lifesaving devices. It is used in all areas of the health care field. X-rays are beneficial for seeing the insides of our body and also for dental purposes. It is also used for security purposes such as the body and baggage screening at the airport. Astronomers use the electromagnetic spectrum for observation purposes. They use radio and microwave telescopes. They also utilize infrared (one of the most dangerous) wavelengths to measure the temperature of planets or to peer through the Milky Way.

While there are numerous benefits of the electromagnetic spectrum, there is also many dangers if overexposed. You can protect yourself from the sun's ultraviolet rays by limiting exposure, using a reliable sunscreen, wearing rash guards while swimming, hats, and light, long sleeved clothing for prolonged periods. Also, do not use tanning beds! There is no health benefit to using tanning beds and they age your skin faster and lend aid to the higher risk of skin cancer. When getting x-rays make sure they are using up to date, serviced equipment and always ask questions regarding why and if it is really necessary to get the work done in the first place. Be sure to use a lead apron for protection of other body parts. To protect yourself against infrared lights unplug electronics when not in use, don’t over expose yourself to toasters, heating lamps, blow dryers and hair straighteners, and other like electronics. Gamma rays are the most dangerous. Some gamma rays would take a thick lead wall to protect you, such as nuclear bombs. Stay away from the highest level of gamma rays, limit exposure (time), distance yourself, and use shields when you are aware that you will be coming in contact with the rays.

While electromagnetic radiation plays a pivotal role in our daily lives by helping us to perform a vast array of tasks and quite literally sustaining our very lives, we must take care to arm ourselves against the negative side effects that come with such high intensity of energy levels. Due to the invisibility to the naked eye of a majority of the energy types on the electromagnetic spectrum, it is crucial to utilize the tools that we have developed to combat the harmful effects and also to limit the time that we spend around the wavelengths produced. Once the type of radiation is determined by the frequency of its wavelength, the proper tool of detection, such as the Geiger-Muller tube or photographic film previously discussed, can be selected and one can better assess the needed protocol to ensure safety of its use. As long as

one is educated and aware of the makeup of the waves that they interact with, electromagnetic waves are a great asset to our lives at the present and help to solidify the progress of our future endeavors.