Name ________________________________________ Date _________________
Unit 4: Astronomy I
Electromagnetic Spectrum
Target: I can compare the wavelengths of different forms of electromagnetic energy.
Do Now: OPEN THE ESRT to page 14. Write down 3 observations about the Electromagnetic
Spectrum reference table at the bottom of the page.
1.
2.
3.
Electromagnetic Waves
Electromagnetic energy is a form of energy that travels in waves at the speed of light. Any light
we see, including the light we see from stars, has traveled to our eyes through electromagnetic
waves. The relationship between the length of waves and their energy is indirect. As the
wavelength increases, the amount of energy decreases.
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Below is a diagram of electromagnetic radiation energies taken from page 14 of the ESRT. There
are 6 shaded types of electromagnetic radiation. Categorize the radiation types in the table below.
1.
Shorter wavelength
Higher Energy
Longer wavelength
Lower energy
2. Draw a squiggly line on top of the electromagnetic spectrum diagram below that demonstrates
the change in wavelength from left to right.
Read This!
Visible light, the light we see with our eyes, is also a form of electromagnetic radiation. The
wavelength of visible light is in the middle, between ultraviolet and infrared radiation.
3. Which color of visible light has the most energy?
4. Explain your answer to #2.
Check with your teacher before you continue.
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5. Put the following electromagnetic radiation categories in order from shortest wavelength to
longest wavelength
Blue light
Ultraviolet
Infrared
6. Which graph best represents the relative wavelengths of the different forms of electromagnetic
energy?
a.
b.
Read This!
The Sun gives off a wide range of electromagnetic energy, but not every type reaches Earth’s
surface.
The diagram below shows the types of electromagnetic energy given off by the Sun. The shaded
part of the diagram shows the approximate amount of each type actually reaching Earth's surface.
7. Which type of electromagnetic energy makes up the greatest amount of electromagnetic
energy reaching Earth's surface?
8. Out of all the types of the Sun’s electromagnetic radiation that reach Earth’s surface, why do
you think ultraviolet radiation is the only one that is harmful?
Check with your teacher before you continue.
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9. Which type of electromagnetic radiation has the longest wavelength?
A) ultraviolet
B) gamma rays
C) visible light
D) radio waves
10. Infrared, ultraviolet, and visible light are all part of the solar spectrum. The basic difference
between them is their
A) wavelength
B) speed
C) source
D) temperature
11. In which list are the forms of electromagnetic energy arranged in order from longest to shortest
wavelengths?
A) gamma rays, x-rays, ultraviolet rays, visible light
B) radio waves, infrared rays, visible light, ultraviolet rays
C) x-rays, infrared rays, blue light, gamma rays
D) infrared rays, radio waves, blue light, red light
12. Energy is transferred from the Sun to Earth mainly by
A) molecular collisions
B) density currents
C) electromagnetic waves
D) red shifts
13. Which type of electromagnetic radiation has the shortest wavelength?
A) ultraviolet
B) gamma rays
C) radio waves
D) visible light
14. Which color of the visible light has the shortest wavelength?
A) violet
B) green
C) yellow
D) red
Check with your teacher before you continue.
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