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Electromagnetic WavesBelieve it or not, you are being “showered”
all the time, not by rain but by waves.
What Is an Electromagnetic Wave?An electromagnetic wave is a transverse
wave made of vibrating electric and magnetic fields that move through space at the speed of light.
• When an electric charge vibrates or accelerates it creates electric fields and magnetic fields that make electromagnetic waves, also known as electromagnetic radiation.• The electric and magnetic fields regenerate,
recharge, repair or fix each other so the waves can travel long distances.
• Unlike mechanical waves, EM waves can travel through a vacuum, or empty space, and also through matter, for long distances.
• Unlike mechanical waves, EM waves can travel through a vacuum, or empty space, and also through matter, for long distances.• EM waves do not transfer energy by vibrations.
Instead, EM waves transfer energy by radiation called electromagnetic radiation.
• Unlike mechanical waves, EM waves can travel through a vacuum, or empty space, and also through matter, for long distances.• EM waves do not transfer energy by vibrations.
Instead, EM waves transfer energy by radiation called electromagnetic radiation.• All EM waves travel at the same speed in the same
medium.
• Unlike mechanical waves, EM waves can travel through a vacuum, or empty space, and also through matter, for long distances.• EM waves do not transfer energy by vibrations.
Instead, EM waves transfer energy by radiation called electromagnetic radiation.• All EM waves travel at the same speed in the same
medium.• EM waves travel at the speed of light in a vacuum.
• Unlike mechanical waves, EM waves can travel through a vacuum, or empty space, and also through matter, for long distances.• EM waves do not transfer energy by vibrations.
Instead, EM waves transfer energy by radiation called electromagnetic radiation.• All EM waves travel at the same speed in the same
medium.• EM waves travel at the speed of light in a vacuum.• Visible light waves emit particles called photons.
What Is the Electromagnetic Spectrum?
The electromagnetic spectrum is the complete range of electromagnetic waves placed in order of increasing frequency.
Electromagnetic WavesElectromagnetic waves are all around you–in
your home, your neighborhood, and your town.
RADIO WAVES: • Have the longest wavelengths, from kilometers long
to a millimeter.
RADIO WAVES: • Have the longest wavelengths, from kilometers long
to a millimeter. • Have the lowest frequency, from 3 megahertz (3
million hertz) to 300,000 megahertz (3 trillion hertz).
RADIO WAVES: • Have the longest wavelengths, from kilometers long
to a millimeter. • Have the lowest frequency, from 3 megahertz (3
million hertz) to 300,000 megahertz (3 trillion hertz).• Have the lowest energy.
RADIO WAVES: • Have the longest wavelengths, from kilometers long
to a millimeter. • Have the lowest frequency, from 3 megahertz (3
million hertz) to 300,000 megahertz (3 trillion hertz).• Have the lowest energy.• Includes radio and television transmission,
microwaves, cell phones, radar.
INFRARED RAYS: • Higher frequency and shorter wavelength than
radio waves.
INFRARED RAYS: • Higher frequency and shorter wavelength than
radio waves.• Size from 1 mm to 750 nanometers.
INFRARED RAYS: • Higher frequency and shorter wavelength than
radio waves.• Size from 1 mm to 750 nanometers.• Infrared waves are also known as heat waves.
INFRARED RAYS: • Higher frequency and shorter wavelength than
radio waves.• Size from 1 mm to 750 nanometers.• Infrared waves are also known as heat waves.• All objects give off infrared waves.
VISIBLE LIGHT: • Part of the EM spectrum that humans can see.
VISIBLE LIGHT: • Part of the EM spectrum that humans can see.• White light is actually made of different colors, like
a rainbow.
VISIBLE LIGHT: • Part of the EM spectrum that humans can see.• White light is actually made of different colors, like
a rainbow.• Each color of light has different frequency and
wavelength, with red being the lowest frequency/longest wavelength and violet the highest frequency/shortest wavelength.
ULTRAVIOLET RAYS: • Higher frequency and shorter wavelength than
visible light.
ULTRAVIOLET RAYS: • Higher frequency and shorter wavelength than
visible light.• Also known as UV radiation.
ULTRAVIOLET RAYS: • Higher frequency and shorter wavelength than
visible light.• Also known as UV radiation.• UV radiation causes sunburn and too much
exposure may cause skin cancer.
ULTRAVIOLET RAYS: • Higher frequency and shorter wavelength than
visible light.• Also known as UV radiation.• UV radiation causes sunburn and too much
exposure may cause skin cancer.• UV radiation is used to kill bacteria.
X-RAYS: • Very short wavelength and very high frequency.
X-RAYS: • Very short wavelength and very high frequency.• High frequency means high energy, so X-rays can
penetrate through most substances.
X-RAYS: • Very short wavelength and very high frequency.• High frequency means high energy, so X-rays can
penetrate through most substances.• Used to take pictures inside the body.
X-RAYS: • Very short wavelength and very high frequency.• High frequency means high energy, so X-rays can
penetrate through most substances.• Used to take pictures inside the body.• Too much exposure can damage living cells.
GAMMA RAYS: • Highest frequency and shortest wavelength of all
EM radiation.
GAMMA RAYS: • Highest frequency and shortest wavelength of all
EM radiation.• Highest energy so gamma rays can penetrate most
substances.
GAMMA RAYS: • Highest frequency and shortest wavelength of all
EM radiation.• Highest energy so gamma rays can penetrate most
substances.• Causes damage to living cells, so gamma rays are
used to kill cancer cells.