The Electromagnetic Spectrum

The Electromagnetic Spectrum

• The Electromagnetic Spectrum is an arrangement of radiant energy in order of wavelengths and frequencies. It is simply a way to help put the different types of energy in order.

• It is similar to how a number line puts numbers in order or the way a time line puts dates in order.

The Electromagnetic Spectrum

• The wavelengths are longest on the left hand side of the Electromagnetic Spectrum and they gradually get shorter towards the right side.

The Electromagnetic Spectrum

• The frequencies on the left are very low and they get higher as you move to the right side of the spectrum.

TV and Radio WavesThese waves have the longest wavelength and lowest frequency. These waves are used to communicate.

TV and Radio Waves• Radio waves carry the news, ball

games and music you listen to on the radio.

• TV waves carry signals to television sets to watch our favorite shows and movies.

Microwaves• These waves help us heat food we eat

very quickly. • They are also used for radar images used

by Doppler radar to forecast the weather. • Cellular phones also used the waves to

allow us to communicate with each other.

Infrared Waves• Infrared waves can be detected as heat. • A radiator, heater and toaster gives off

infrared waves. • Infrared imaging can be observed using

a special film that shows objects in different colors.

Visible Light or Visible Spectrum

• These waves are the only electromagnetic waves we can see. We see them as the colors of the rainbow.

• Each color has a different wavelength. Red has the longest wavelength and violet has the shortest wavelength. These waves combine to form white light.

Ultraviolet Waves• These waves are invisible to the

human eye, but some insects can see them like the bee.

• The waves that come from the sun cause sunburns.

• These waves also come from tanning beds.

• These waves can cause skin cancer.

X-Rays• Doctors use x-rays to look at your

bones .• Dentists are able to look at your

teeth to help detect cavities and identify problems with teeth coming in or shifting.

• X-rays can damage cells.

Gamma Rays• These waves are radioactive. • Nuclear power plants use use

uranium as a fuel source which gives off Gamma Rays.

• Doctors can use gamma rays to kill diseased cells like cancer.

• Gamma rays kill living cells.• Gamma rays are used to sterilize

surgery tools.

The Electromagnetic Spectrum