Microwaves

By Radha Sharma, Alison Valley and Elizabeth Shenson

Microwaves

Range of wavelengths: 1m-1mm Range of frequency: 300MHz - 300GHz Between radio waves and infared waves in

Electromagnetic Spectrum

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Uses of Microwaves• Communications

• Microwaves were used because their long wavelengths allowed them to travel far while being accurate to their location.

• Radar• Microwaves can detect the speed and range of remote

objects• Air traffic control, automatic doors and weather

forecasting find microwave radar useful.

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• Microwave ovens• These types of ovens send microwave radiation waves

though food causing it to heat up.• Microwave ovens heat up everyday food making

cooking much easier.

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WiFi connection At a low intensity, the high frequency of microwaves

allows the connection to travel to far places and create internet sources.

Government communication Government officials rely on microwaves high

frequency to communicate through long distance phone calls.

Are radio waves damaging to humans?

Low energy can cause severe burning Can heat human body organs; may cause

damage is body is unable to dissipate heat Can cause hearing sensations Research is being done to see if the waves

cause harm to the immune system and central nervous system.

Who?

• Heinrich Rudolf Hertz, a German physicist, is responsible for the proving and demonstrating the existence of microwaves in 1886

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How were microwaves discovered?

In 1865, a British mathematician named James Clerk Maxwell theorized the existence of electromagnetic by means of equations

Assuming that Maxwell’s ideas were correct, Hertz carried out an experiment to produce these waves

The Experiment

The experiment consisted of an oscillator made of brass knobs that were connected to an to an in induction coil and separated by a gap, over which sparks could jump

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When the sparks appeared on the receiver, it was clear that electromagnetic waves were being transmitted

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Interesting Facts

The SETI (Search For Extraterrestrial Intelligence) uses microwaves to search for aliens

Since microwaves do not occur in nature, any evidence of them could mean extraterrestrial life

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