Transcript Unit 4 Waves Ch. 22 Sec. 2 The Electromagnetic Spectrum Electromagnetic Waves are EVERYWHERE! The Electromagnetic Spectrum • electromagnetic spectrum - the range of all EM. waves w/

Unit 4
Waves
Ch. 22 Sec. 2
The Electromagnetic Spectrum
Electromagnetic
Waves
are
EVERYWHERE!
The Electromagnetic Spectrum
• electromagnetic spectrum - the range of all EM.
waves w/ different frequencies & wavelengths
– all EM. waves are produced by moving charged particles
– faster particle movement = higher frequency = more energy
– increasing frequency/energy = decreasing wavelength
The Electromagnetic Spectrum
EMS:  Radio Waves
• radio waves - EM. waves
w/ the longest wavelength,
lowest frequency, & least
energy
– Longer than 30cm
– 104Hz
• ex. TV signals, AM/FM radio
signals, cell phone signals
• used in most forms of
telecommunications
technology
EMS:  Microwaves
• microwaves - type
of radio waves used
in some cell phones
& in microwaves
– 1mm – 30cm
– 108Hz
EMS:  Infrared Waves
• infrared waves - EM.
waves given off by
almost every object
– 700nanometers – 1mm
– 1012Hz
• ex. heat from a warm
fire, warmth from a
body
• used to map wildfires,
locate prey (pit vipers),
change TV channels,
etc.
EMS:  Visible Light
• visible light - EM. waves that
result when an object is heated
making electrons move faster
– 400nm – 700nm
– Varies depending on color
• only EM. waves that can be seen
• most objects do not give off visible
light, but rather reflect it = color
• different wavelengths = colors
EMS:  Ultraviolet Radiation
• ultraviolet radiation - EM.
waves w/ enough energy to
damage cells
– 60nm – 400nm
– 1016Hz
• makes up a portion of
sunlight
• unlike visible light & radio
waves, most UV radiation is
absorbed by the atmosphere
(ozone layer)
• used to sterilize surgical
equipment, aid in vitamin D
production, etc.
EMS:  X Rays
• X rays - EM. waves w/
enough energy to penetrate
skin & muscles
– 0.001nm – 60nm
– 1018Hz
• used to view bones
• like ultraviolet radiation, can
be harmful to cells
EMS:  Gamma Rays
• gamma rays - EM. waves
w/ the shortest wavelength,
highest frequency & most
energy
– Shorter than 0.001 nm
– 104Hz
• produced by changes in
atomic nuclei
• can be deadly to cells
• used to destroy cancer cells
& bacteria on meat, etc.
EMS: THE GOOD AND THE BAD
EM Spectrum Foldable
• 8 Tabs
1.
2.
3.
4.
5.
6.
7.
8.
Electromagnetic Waves
Radio Waves
Microwaves
Infrared Waves
Visible Light
Ultraviolet Waves
X-rays
Gamma Rays
• On Each Tab Include:
– Frequency/Wavelength
– 2 Examples
– 1 Interesting/Fun Fact