I. INTRODUCTION


Current technological advances increased following the use of wave elekromagnetik in everyday life.
As to whether the electromagnetic waves, what examples of electromagnetic waves that?Electromagnetic waves in fact there is always around us, one example is the sun's rays, these waves do not require an intermediary in perambatannya medium. Another example is radio waves. But the spectrum of electromagnetic waves are composed of various other types of waves, which are distinguished by frequency or wavelength. For that here we will learn about the range of the spectrum of electromagnetic waves, special characteristics of each of the electromagnetic waves in the spectrum and examples and application of each of the electromagnetic waves in everyday life.





            II. STUDY REFERENCES


ELECTROMAGNETIC WAVES


Electromagnetic waves are waves that can propagate even if there is no medium. Electromagnetic energy travels in waves with some characters that can be measured, namely: wavelength / wavelength, frequency, amplitude / amplitude, velocity. Amplitude is the height of the wave, while the wavelength is the distance between two peaks. Frequency is the number of waves passing through a point in one unit of time. The frequency depends on the speed of the wave climbed. Because the speed of electromagnetic energy is a constant (speed of light), wavelength and frequency is inversely proportional. The longer a wave, the lower the frequency, and the shorter the wave the higher frequencies.
Electromagnetic energy emitted, or released, by all the time in the universe on a level that berbedabeda. Higher levels of energy in an energy source, the lower the wavelength of the energy produced, and the higher frequencies. Different characteristics of the wave energy is used to classify the electromagnetic energy.
The characteristics of electromagnetic waves:From the description above we can conclude several characteristics of electromagnetic waves is as follows:
1. Changes in electric and magnetic fields occur at the same time, so that the two fields have a maximum and minimum prices at the same time and at the same place.
2. Direction of electric field and magnetic fields perpendicular to each other and both perpendicular to the direction of propagation.
3. Of characteristic No. 2 obtained that electromagnetic waves are transverse waves.
4. Like the waves in general, an incident electromagnetic wave reflection, refraction, interference, and diffraction. Also experienced events including the polarization due to transverse waves.
5. Rapid propagation of electromagnetic waves depends only on the properties of electric and magnetic medium which he passes.
Visible light by the eye is not simply the type that allows electromagnetic radiation. The opinion of James Clerk Maxwell showed that electromagnetic waves other, in contrast to visible light by the eye in she had a wavelength and frequency, there may be. These theoretical conclusions were remarkably reinforced by the Heinrich Hertz, which is able to produce and meet the two waves are visible to the eye that was predicted by Maxwell. A few years later Guglielmo Marconi demonstrated that the waves are invisible eye that can be used for communication without wires, so what's his name menjelmalah radio. Now, we use also for television, X-rays, gamma rays, infrared rays, ultraviolet rays are examples of electromagnetic radiation. Everything can be learned through the ideas of Maxwell.





 SOURCE ELECTROMAGNETIC WAVES

   1. Electrical oscillations.
   2. Sunlight  generating infrared rays.
   3.  mercury lamp produces ultra violet.
   4. The shooting of electrons in vacuum tubes on the metal pieces  produce X-rays (used for x-rays).
An unstable atomic nuclei produce gamma rays.


ELECTROMAGNETIC WAVE SPECTRUM
The composition of all forms of electromagnetic waves by their wavelengths and frequencies called the electromagnetic spectrum. Electromagnetic spectrum images below is based on the wavelength (measured in units _M) includes a very low energy range, with wavelengths of high and low frequencies, like radio waves up to very high energies, with a low wavelength and high frequency radiation such as X -ray and Gamma Ray.


Examples of the electromagnetic spectrum


Radio waves
Radio waves are classified according to wavelength or frequency. If the wavelength is high, then surely the low-frequency or vice versa. Frequency radio waves ranging from 30 kHz up and grouped according to the width of the frequency. Radio waves generated by electric charges are accelerated through the wire-wire conductor. Charges are generated by the electronic circuit called an oscillator. These radio waves emitted from the antenna and received by the antenna anyway. You can not hear the radio directly, but the receiver will change the first radio wave energy into sound energy.


Microwaves
Microwaves (mikrowaves) is a radio wave with the highest frequency that is above 3 GHz. If the microwaves are absorbed by an object, it would appear the effect of heating on the thing. If the food absorb microwave radiation, then the food gets hot in a very short time interval. The process is utilized in a microwave oven to cook food quickly and economically.
Microwaves are also used in aircraft RADAR (Radio Detection and ranging) Radar is looking for and determine the footprint of an object by using microwaves. Aircraft utilizing radar reflection properties of microwaves. Due to rapid propagation of electromagnetic glombang c = 3 X 108 m / s, then by observing the time interval between transmitting the reception.

 Infrared rays
Infrared beam covers an area up to 1014 Hz 1011Hz frequency or wavelength region 10-4 cm to 10-1 cm. if you check the spectrum produced by an incandescent lamp with a detector which is connected to the miliampermeter, then the needle ampermeter slightly above the red end of the spectrum. Rays are not visible but can be detected above the red spectrum is called infrared radiation.Infamerah rays produced by electrons in the molecules vibrate due diipanaskan objects. So any hot objects emit infrared light definitely. The amount of infrared light emitted depends on the temperature and color of objects.


Visible light
Visible light as electromagnetic radiation of the best known by us can be defined as part of the electromagnetic wave spectrum that can be detected by the human eye. The wavelength depends on the color looks nervariasi wavelengths ranging from approximately 4 x 10-7 m to light violet (purple) to 7x 10-7 m for a red light. Usefulness of light one of them go round the use of lasers in optical fibers in telecommunications and medicine.

Ultraviolet light
Ultraviolet light has a frequency in the region of 1015 Hz to 1016 Hz or in the length of gelombagn 10-8 m 10-7 m These waves generated by atoms and molecules in an electric flame. The sun is the major source that emits ultraviolet rays on the surface of the earth, the ozone layer is in the top layer that serves atmosferlah absorb ultraviolet rays and ultraviolet rays that do not continue to endanger the lives of living beings on earth.

X-ray
X-rays have a frequency between 10 Hz to 10 Hz. very short wavelength of 10 cm to 10 cm. although as it is but an X-ray has a strong penetrating power, can penetrate thick books, a few centimeters thick wood and aluminum plates 1 cm thick.

 Gamma rays
Gamma rays have a frequency between 10 Hz to 10 Hz or a wavelength of between 10 cm to 10 cm. Greatest penetrating power, which causes serious effects if absorbed by body tissues.


Examples of the application of electromagnetic waves in everyday life:

   1.
         1. Radio
Radio energy is the lowest form of electromagnetic energy levels, with a wavelength range from thousands of kilometers to less than one meter. The use most is communication, to examine the space and radar systems. Radar is useful for studying weather patterns, storms, making a 3D map of the earth's surface, measuring rainfall, movement of ice in the polar regions and environmental monitor. Radar wavelength range between 0.8 - 100 cm.

   1.
         1. Microwave
Microwave radiation wavelength range between 0.3 - 300 cm. Its use is mainly in the fields of communication and information delivery through open space, cooking, and the system is active PJ. PJ active on the system, a microwave pulse is fired through a target and its reflection is measured to study the characteristics of the target. As an application example is the Tropical Rainfall Measuring Mission's (TRMM) Microwave Imager (TMI), which measures the microwave radiation emitted from the electromagnetic spectrum of electromagnetic energy of the earth's atmosphere to measure evaporation, water content in clouds and rain intensity.

   1.
         1. Infrared
Health conditions can be diagnosed by investigating the infrared emission from the body. Special infrared photo called thermogram is used to detect blood circulation problems, arthritis and cancer. Infrared radiation can also be used in burglar alarms. A thief without his knowledge will prevent light and hide the alarm. Communicate with the TV remote control via infrared radiation generated by the LED (Light Emiting Diode) contained in the unit, so that we can turn on the TV from a distance using a remote control.


d. Ultraviolet


UV rays are needed in the assimilation of plants and can kill germs skin diseases.


e. X-ray


X-rays are commonly used in medicine for photographing the position of the bones in the body especially to determine the fracture. However, the use of X-rays should be careful because the tissues of human cells can be damaged by the use of X rays that are too long.





          III. CONCLUSION
From the above discussion, it can be concluded that the electromagnetic waves so large a useful role in our daily lives, without us knowing it existed.
Electromagnetic spectrum is the range of all possible electromagnetic radiation. Electromagnetic spectrum can be explained in wavelength, frequency, or energy per photon. This spectrum is directly related to:

    * The wavelength multiplied by frequency is the speed of light: 300 Mm / s, ie 300 MmHz

    * The energy of the photons is 4.1 FEV per Hz, which is 4.1μeV/GHz

    * The wavelength multiplied by the energy per photon is 1:24 μeVm
Electromagnetic spectrum can be divided into several regions extending from gamma rays of high-energy short-wave to the microwaves and radio waves with extremely long wavelengths. The division is actually not so firm and grew from the practical use of the historis derived from a variety of detection methods. Usually, in describing the electromagnetic spectrum of energy is expressed
in elektronvolt for high-energy photons (above 100 eV), the wavelength for intermediate energy, and the frequency for low energy (? = 0.5 mm). The term "optical spectrum" is also still widely used in referring to the electromagnetic spectrum, although it only covers some of the wavelength range alone (320-700 nm) [1].
And some examples of the electromagnetic spectrum such as:
Radar
(Radio Detection And ranging), is used as transmitter and wave receiver.
Infra Red
Resulting from the vibrations of atoms in the material and used to study the molecular structure
Visible light
has a wavelength of 3990 A º - 7800 º A.
Ultra violet
utilized for the introduction of elements of a material with spectroscopic techniques.



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