Electromagnetic Spectrum Activity
Instruction
The electromagnetic spectrum is the distribution of electromagnetic radiation according to frequency or wavelength. Thus, visible light, gamma rays and microwaves are really the same thing. They are all electromagnetic radiation; they simply differ in their wavelengths.
The electromagnetic spectrum is something that is more familiar than one might think. The light that our eyes can see is actually part of the electromagnetic spectrum. This visible part of the electromagnetic spectrum consists of the colours we see in a rainbow - from reds and oranges, through blues and purples. Each of these colors actually corresponds to a different wavelength of light.
The main picture represents the electromagnetic spectrum. Slide the curser or click the red dots in the spectrum to see images or representations of the frequency chosen.
Here is a description of the different wavelengths in the spectrum:
Text of this activity
104m
10 000 m or 10 km
This distance is about as long as the Confederation bridge
102m
100 m
This distance is about as long as a soccer field
100m
1 m
This distance is on the same scale as the average height for a North American person (1.7-1.8 m)
10-2m
1 cm (from the Latin word for hundred)
This is about the same size as a pea.
10-3m
1 mm (from the Latin word for thousand)
This is about the same size as dust particles
10-6m
1 µm (micrometre from the Greek word for small) or 1 thousandths of a millimetre
This is about the size of bacteria
10-9m
1 nm (nanometre from the Greek word for dwarf) or 1 millionth of a millimetre
This is about the size of a typical molecule
10-10m
1 angstrom (from the name of a Swedish physicist)
This is about the size of an atom
10-12m
1 picometre (from the Italian word for small)
This is about the size of an electron or proton
10-15m
1 fm (femtometre, from the Danish word for fifteen)
This is about the size of a nucleon
10-18m
1 am (attometre, from the Danish word for eighteen)
This is about the size of a quark
10-21m
1 zm (zeptometre, a term invented for spectrometry)
This size does not correspond to any known thing
10-24m
1 ym (yoctometre, an invented term)
This size does not correspond to any known thing
104m
10,000 metres or 10 kilometres
Measured in metres, this represents 10,000 metres or 10 kilometres—the diameter of a celestial object that crashed into the Yucatan Peninsula 65 million years ago causing the extinction of the dinosaurs.
106m
1,000,000 m or 1,000 kilometres
Measured in metres, this represents 1,000 kilometres—the diameter of Ceres, the largest asteroid in the asteroid belt between Mars and Jupiter.
108m
100,000 kilometres
Measured in metres, this represents 100,000 kilometres—the distance by which asteroid 1994 XM missed the Earth in 1994.
1010m
10 million kilometres
Measured in metres, this represents 10 million kilometres—the thickness of the Sun’s corona. A solar corona is the outer layer of a sun’s atmosphere. It resembles a halo of pearly light and is only visible during total eclipses of the Sun.
1012m
1 billion kilometres
Measured in metres, this represents 1 billion kilometres—the approximate distance travelled by the Earth around the Sun in one year.
1014m
100 billion kilometres
Measured in metres, this represents 100 billion kilometres—the distance separating the Earth from the heliopause, the outer limit of the solar system where solar wind is stopped by the interstellar medium.
1016m
10,000 billion kilometres
Measured in metres, this represents 10,000 billion kilometres—the distance travelled by light in one year, also known as 1 light-year.
1018m
100 light-years
Measured in metres, this represents 100 light-years—the diameter of nebula NGC 7000, also known as the “North America Nebula”.
1020m
10,000 light-years
Measured in metres, this represents 10,000 light-years—the distance separating us from globular cluster M22.
1022m
1 million light-years
Measured in metres, this represents 1 million light-years—the average distance between galaxies.
1024m
100 million light-years
Measured in metres, this represents 100 million light-years—the distance between us and galaxy NGC 5850 in the Virgo constellation.
Gamma rays
The most energetic form of light. Invisible, it is generated by subatomic particles or atomic nuclei. Radioactive chemical elements produce gamma rays.
The sun under Gamma rays
X-rays
Highly energetic invisible light that can pass through many types of material. This quality enables it to be used (in small doses) for medical imaging.
The sun under X-rays
Ultraviolet
Energetic invisible light found just beyond the colour violet in the electromagnetic spectrum. Prolonged exposure to ultraviolet light can cause health problems in the human body, particularly for the eyes and skin. Luckily for us, a large amount of ultraviolet rays produced by the Sun is absorbed by ozone, one of the gases in our atmosphere.
The sun under Ultraviolet
Visible
Light that can be perceived by the human eye. It includes all the colours of the rainbow, from violet to red.
The sun Visible
Infrared
Invisible light that lies just beyond the colour red in the electromagnetic spectrum. It is often associated with heat because most objects at ambient temperature will emit infrared light when heated.
The sun under Infrared
Microwave (1 mm–1 cm)
Relatively non-energetic invisible light. It is used for a wide variety of technological applications. In microwave ovens, for example, it agitates water molecules, creating heat and thus warming the food.
Radio (1 cm +)
Relatively non-energetic invisible light. Radio waves are mainly used in the field of communications because they can travel easily and are not absorbed by the atmosphere.
The sun under Radio waves
Radar (1 cm–10 cm)
Invisible light used to detect objects, like planes, boats or even rain.
TV (10 cm–1 m)
Invisible light that carries television signals.
FM (1 m–10 m)
Invisible light that carries FM radio signals.
Short (10 m–100 m)
Invisible light that carries, among other things, amateur radio operator signals.
AM (100 m -1 km)
Invisible light that carries AM radio signals.
Transportation (1 km +)
Invisible light that carries, among other things, radio signals used for navigation (for example, aircraft and shipping bands).
© 2006 An original idea and a realization of the ASTROLab of Mont-Mégantic National Park