Microwaves

1
Microwaves

• By Radha Sharma, Alison Valley and Elizabeth
  Shenson

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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.

4

• Radar
• Microwaves can detect the speed and range of
  remote objects
• Air traffic control, automatic doors and weather
  forecasting find microwave radar useful.

5

• 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.

6

• WiFi connection
• At a low intensity, the high frequency of
  microwaves allows the connection to travel to far
  places and create internet sources.

7

• Government communication
• Government officials rely on microwaves high
  frequency to communicate through long distance
  phone calls.

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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.

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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 Maxwells ideas were correct, Hertz
  carried out an experiment to produce these waves

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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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