10/20/2014
Electromagnetic
spectrum!
Many types of light
Light Boggle
At your table, write down as many different types of electromagnetic
radiation as you can think of.
Do not use your textbook!!!
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10/20/2014
Fun Fact
• Galileo tried to measure the speed of light
Introduction
• Sunlight consists of all the different kinds
of light.. Fortunately, Earth’s atmosphere
prevents most of the harmful radiation
from reaching Earth’s surface.
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10/20/2014
Electromagnetic Radiation
• Most electromagnetic
radiation –(energy that travels
in waves)-. on Earth comes
from the sun. Like other waves,
electromagnetic radiation is
characterized by certain
wavelengths –(the distance
between two peaks on a wave).
Longer
Wavelength
Shorter
Wavelength
Frequencies
•
Different wavelengths have different
amounts of energy and wave frequencies –
(the number of waves that pass a fixed
point in a given amount of time)- .
Electromagnetic waves with shorter
wavelengths have higher frequencies and
more energy. For example, to generate a
higher-frequency wave in a rope, you must
move the rope up and down more quickly.
This takes more energy, so a higher
frequency wave has more energy than a
lower frequency wave.
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10/20/2014
Examples of emitters and what we can
• FM vs AM
• Red Laser vs Green Laser
• Red bull vs Ultraviolet bull
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10/20/2014
Spectrum
• On the left side of the electromagnetic spectrum diagram are radio waves
and microwaves. Radio waves have the longest wavelengths and lowest
frequencies of all electromagnetic waves. They also have the least amount
of energy.
• On the right side of the diagram are X- rays and gamma rays. They have the
shortest wavelengths and highest frequencies of all electromagnetic waves.
They also have the most energy.
• Between these two extremes are waves that are commonly called light.
Light includes infrared light, visible light, and ultraviolet light. The
wavelengths, frequencies, and energy levels of light fall in between those of
radio waves on the left and X rays and gamma rays on the right.
• (visible light spectrum & Energy = ROYGBIV)
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10/20/2014
Summary
• Electromagnetic radiation travels in waves
through space or matter. Electromagnetic waves
with shorter wavelengths have higher frequencies
and more energy.
• The full range of electromagnetic radiation is
called the electromagnetic spectrum. From
longest to shortest wavelengths, it includes radio
waves, microwaves, infrared light, visible light,
ultraviolet light, X- rays, and gamma rays.
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