8th Grade Honors Science
Name_____________________________
Waves we can’t see – Notes
-The electromagnetic spectrum is the ______________________________________________.
-It is divided into regions according to the _________________________________. All EM
waves travel at the same speed in a vacuum – but the _____________ and _____________
differ.
-The EM spectrum goes from ___________ /______________ to ______________/__________.
Radio Waves-Have the longest wavelength, lowest frequency of all EM waves. Radio waves have a
wavelength longer than __________. Radio stations vary the waves’ ___________ or
__________ - this change is called ________________.
AM ___________________________________________________________________
FM ___________________________________________________________________
-Television – carried by radio waves. Use ________________ wavelengths and ___________
frequencies than radio stations.
-TV stations use FM waves to carry ____________ and AM waves to carry ______________.
Microwaves-Shorter ______________ and higher __________ than radio waves. Wavelength between
__________ and ____________.
Examples of microwaves:
8th Grade Honors Science
Name_____________________________
Infrared Waves-Wavelengths between ________ and _______________. 1 nanometer is ______________m.
-Sun’s rays are infrared – this is what heats your body. The waves cause the particles in your
skin to ________________________. Almost all objects give off ______________________.
Not visible to the naked eye.
Visible Light-Very narrow range of wavelengths and frequencies that _________________________.
-Wavelengths between _______________ and ___________________. Visible light from the
sun is called __________________, which is a combination of all visible light wavelengths.
-Humans can see the different wavelengths of visible light as __________________. The
Longest wavelength is ________ - shortest wavelength is _______________. This range of
colors is called the ________________________.
Ultraviolet Light
-Wavelengths vary between ____________ and ____________.
-Bad effects on humans –
-Good effects on humans-
X-Rays
-Wavelengths between _________ and __________ . Because they are so small, they can pass
through many materials, including human soft tissue.
Examples of x-ray uses:
Gamma Rays
-Shortest wavelengths – shorter than _____________.
-Can penetrate most materials very easily – used to treat ________________ and to kill
______________.