Electromagnetic Spectrum

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Electromagnetic Spectrum

• Everything from Radio waves to Gamma Rays

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Electromagnetic Spectrum

• Name for the range of electromagnetic waves when
  they are placed in order of increasing frequency

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Electromagnetic Spectrum Continued
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EM Wave Energy
Frequency Energy
Wavelength
High Freq
Low Freq
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Radio Waves

• Waves with the longest wavelengths and lowest
  frequency

Low Energy
AM Amplitude Modulation
FM Frequency Modulation
Travel very well through the air!!!
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Microwaves

• Waves with shorter wavelengths and higher
  frequencies than radio waves

• Uses
• Communications
• -- Satellite to Earth
• -- TV signals
• 2. Aircraft radar
• -- Stealth aircraft absorb microwaves
• Signal does not bounce/reflect back

High Energy
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Microwave Ovens
- MW absorbed by water, fat, sugar molecules MW
excites molecules Food heats ( kinetic energy
) - Metal reflects MW
MW Generator
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Infrared Waves

• Waves that are responsible for heat/thermal energy

Our skin absorbs IR....we can "feel" it, but we
cannot "see" it
We have detectors to "see" IR
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Infrared/Night Vision
- Sees infrared or heat - Converts it to
visible light
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Examples of IR Readings
Body Temperature
City Temperature
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Visible Light
White Light
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Ultraviolet Radiation

• Our eyes cannot "see" UV radiation

High Energy
UV-A
UV-B
Can be absorbed by our skin!!
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Wear Sunscreen!
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X-Rays

• Very high energy (high-frequency)

Are absorbed by the body by tissues while bones
and teeth transmit this energy
Very Dangerous!!!!
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Gamma Rays
Extremely

• High Energy

Can be used for medical treatment of cancer
Very uncommon in nature