ElEcTROMAGNETIc WAVE
Electricity can be static, like the energy that can make
your hair stand on end. Magnetism can also be static, as it
is in a refrigerator magnet. A changing magnetic field will
create a changing electric field and vice-versa, the two are
linked. These changing fields form electromagnetic waves.
ElEcTROMAGNETIc sPEcTRuM
Electromagnetic energy travels in
waves and spans a broad spectrum
from very long radio waves to very
short gamma rays. The human eye can
only detect a small portion of this
spectrum called visible light.
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2
name of
wave
Radio Waves
Microwaves
Infrared
Visible Spectrum
Ultra Violet
X-rays
Gamma
wavelength
(meters)
about the
size of
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Light is also � ergy th at tr ave ls in wa� s. �ou
can not see the
se �ave s li� you c� see ocean
wave s� but you can see the
ir en ergy as �isible li�ht.
fo otball � el d
you!
bee
c� l �hon e
T�
remote
el ec� ic � � d
Light we can see!
vid� game
con tr oller
radio
magn� ic � el d
pin � ad
c� l
bacteria
virus
atom
nuclei
electromagnetic energY
When you tune your radio, watch TV, send a text message, or pop popcorn in a microwave
oven, you are using electromagnetic energy. Without it, the world you know could not exist.
11
S
C
i
ENC
E iN
a
C
T
iO
N
try the
Energy Meter
Project p.14
