Radar is a system that is used to determine the direction, range, altitude, or speed of guided missiles, ships, aircraft, spacecraft, motor vehicles, terrain, and weather formations. High-frequency electromagnetic waves are sent by radar, which will reflect off the object back to the source. It was developed before and during World War II.
German physicist Heinrich Hertz in the 1880s was the first one to produce and transmit radio waves. Italian physicist Guglielmo Marconi in 1901 sent the first wireless radio communication across the Atlantic Ocean and it initiated interest among people for further development of radar. In 1904 German engineer Christian Huelsmeyer used radio waves to detect boats and ships in dense fog. Researches for the radar development were being done in several nations at the time. Robert Watson Watt joined the Meteorological Office in 1945 and worked as a meteorologist. He studied atmospheric phenomena for about 20 years and developed systems to detect position of thunderstorms. Watson-Watt demonstrated the first practical radio system for detecting aircraft in February, 1935. He funding for further development and soon he developed the system to detect airplanes up to 80 miles away.
The first radars required long antennas and long wavelengths to detect aircraft. When it became difficult for pilots to locate aircrafts at nighttime, the need for compact radar systems that use shorter wavelengths arose. In 1940, British engineers Harry Boot and John Randall invented the cavity magnetron which produced 400 watts of power at 10 cm wavelengths. It was small enough, so that it can be mounted onto the aircraft. Britain brought the magnetron to the United States for mass production. 100 different radar systems were developed in the MIT Radiation Laboratory, USA. It had played a major role in the victory of World War II. After the war the radar system is used for peaceful reasons. Radar has developed furthermore with the applications of modern day technology and is used for variety of reasons. Three major uses of radar today are for air traffic control, tracking weather, and to make roads safe from speeding people.
Traveling by air is said to be the safest way to travel. It will not be that way if the radar system did not exist. Airplane travel will be one of most dangerous if there was no radar system. There will be constant collisions between airplanes and loss of life. The radar system helps to detect other planes in the sky. The operators will thereby be able to direct pilot on how to fly and land safely.
Weather forecast is part of our everyday life nowadays. We check the weather every day to see if we are going to have a pleasant day or not. Weather radar is used to locate precipitation, calculate its motion, and estimate its type. It is very useful to take precautions when tropical storms and disasters occur. Without weather radar we will not be able to know when the hurricanes are going to occur or other tropical storms are about to occur.
Thousands of people die every day due to car crashes. Many of these crashes are caused by speeding. Radar devices are used by police to detect speeding drivers. Radar gun is a device that is used most commonly by the police to detect speeding drivers. It is small and could be hand held or mount to the car. It is very effective in catching speed violators. Our roads are made safer by the radar devices.
In conclusion, radar systems make our everyday life safer. From road to air, radars are used to control many things around us. Before, radars were only used for defense purposes on wars. Today, radars make systems easier to work. It is also very helpful for research organizations like NASA. Radars help them to map the terrains of planets and moons and to monitor space. Radars have developed since its invention and it is a very useful invention for us.
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