Examples and some technological applications of electromagnetic waves
The electromagnetic waves
Electromagnetic waves are formed when an electric field couples with a magnetic field. The magnetic and electric fields of electromagnetic waves are perpendicular to each other and to the direction of the wave.
Electromagnetic waves are characterized by:
- They are accompanied by electromagnetic forces.
- Their speed is extremely high (the speed of the light is about 300 million m/s).
- No medium is required for the electromagnetic waves to travel through, They can travel through the free space.
Examples of electromagnetic waves :
- Gamma rays
- The light waves
- Wireless waves (which are used in communications)
- Ultraviolet and infrared rays (accompanied by Sun rays).
- Radio and television waves.
Technological applications of electromagnetic waves
Ultraviolet (UV) rays: They have the property of killing the microbes, so, they are used to sterilize the sets of surgical operations rooms.
X-rays: They are very important In photographing the bones for detecting the bone fractures, X-rays are used in examining the mineral raws in industry and showing errors, pores and cracks in these minerals.
Gamma rays: They are used for medical purposes as the treatment and discovery of some swellings (tumors).
Visible (seen) light: They are used In photographing cameras, They are very important in television cameras, They are used in light shows (data show).
Infrared (IR) rays: They are used in night vision apparatus used by modern military forces, They are very important in remote sensing instruments to photograph Earth’s surface using satellites.
Also, they are used in cooking food because these rays have heat effect properties and they are used in making remote sets to control and start electric sets (TV, DVD, air conditioner …. ).