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MICROWAVES
MICROWAVES
DESCRIPTION (NATURE AND PROPERTIES):
The microwave oven was accidentally invented by the scientist named Percy Spencer. Microwaves are a form of "electromagnetic" radiation; that is, they are waves of electrical and magnetic energy moving together through space. Electromagnetic radiation spans a broad spectrum from very long radio waves to very short gamma rays. Microwaves are higher-frequency radio waves, usually generated and produced using electron tubes and special vacuum tubes referred to as klystrons, magnetrons, and Gunn diodes. Microwaves are used in telecommunication, such as mobile phones. Microwaves are made by various types of transmitters-an electronic device which, with the aid of an antenna, produces radio waves.
PROPERTIES OF MICROWAVES:
Microwaves are capable of radiating electromagnetic energy with shorter wavelengths Microwaves are reflected by metal surfaces The transmission of microwaves is affected by phenomena like refraction, diffraction, reflection, and interference Microwaves of certain frequencies are absorbed by water Microwaves can easily pass through glass and plastic.
PERCY SPENCER
Percy Spencer was an American physicist and inventor. He became known as the inventor of the microwave oven. Born: July 19, 1894, Howland, Maine, United States Died: September 8, 1970, Newton, Massachusetts, United States Percy Spencer, while working for the Raytheon Company, discovered a more efficient way to manufacture magnetrons. This discovery led to significant advances in radar and his most popular invention, the microwave oven. In 1941, magnetrons were being produced at a rate of 17 per day.
REGION FREQUENCY (Hz) WAVELENGTH (m) ENERGY (J)
Microwaves 1 × 10⁹ to 3 × 10¹¹ 1 × 10⁻³ to 3 × 10⁻¹ 2 × 10 10 ⁻²² ⁻²⁴ to 2 ×
EXAMPLES OF MICROWAVES:
a. ASTRONOMICAL AND SPACE EXPLORATION
HARMFUL EFFECTS OF MICROWAVES:
The damaging effects of MW radiation on the brain include brain dysfunction and brain structural damage. Microwaves can get rid of 60 - 90% of the nutritional value of what food you put in Microwaves can explode if you put them in a milk bottle or baby food Microwaves can lead food to dehydrate due to the radiation Harmful radiation can harm the body and eyes.
WAYS TO ELIMINATE OR MINIMIZES HARMFUL EFFECTS:
Follow the manufacturer’s instructions for use. Directions in the user manual provide recommended operating procedures and safety precautions. For instance, you should not use some microwave ovens when they are empty. In addition, you should not heat water or liquids longer than the manufacturer’s instructions and recommendations. Avoid super-heated water. “Super-heated” means water is heated beyond its boiling temperature, without signs of boiling. If you use a microwave oven to heat water in a clean cup beyond the boiling temperature, a slight disturbance or movement may cause the water to violently explode out of the cup. There have been reports of serious skin burns or scalding injuries around people’s hands and faces as a result of this phenomenon. Check for leakage. There should be little cause for concern about excess microwave radiation leaking from these ovens unless the door hinges, latch, or seals are damaged. The FDA recommends looking at your oven carefully to see if any of these issues exist. The agency also recommends that you do not use an oven if the door doesn’t close firmly or is bent, warped, or otherwise damaged. Don’t use ovens that seem to operate when the door is open. The FDA monitors these appliances for radiation safety issues and has received increasing reports about microwave ovens that appear to stay on—and operate—when the door is open. The FDA recommends that you immediately stop using a microwave oven if this happens. Make your bedroom an EMF radiation-free oasis. Re-position your bed and bedroom, if needed to be as far as possible from power lines, routers, and smart
meters. If possible move your bed at least a foot away from the wall, the wiring in the wall behind your headboard likely is radiating. Get rid of electronics that would be dangerous to have on or near your body. Try to keep a distance from cell phone towers. Never sleep next to your cellphone. Test your microwave for leaks.
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