Chapter 4 | Electromagnetic (EM) Spectrum

Question 1

Name the two (types) of waves.

Answer 1

1. Mechanical =
   -Needs a medium to travel (air or water)
   -Example: sound from an instrument, earthquakes, rock thrown in water
2. Electromagnetic =
   -Can travel in a vacuum or a medium
   -Example: WiFi, Radio Waves, Light
   (Vacuum = space with no particles)

Question 2

Name the types of waves on the Electromagnetic Spectrum in order from least dangerous to most dangerous.

Answer 2

1. Radio Waves
2. Microwaves
3. Infrared Waves
4. Visible Light
5. Ultraviolet Rays
6. X-Rays
7. Gamma Rays

Question 3

Give some facts about Radio Waves.

Answer 3

• Least dangerous type of wave
• Smallest frequency on the spectrum
• Are invisible and transport little energy
• Raises temperature in matter

Question 4

Give some facts about Infrared Waves.

Answer 4

• We can feel the warmth they emit

- Barely visible to the naked eye

Question 5

Give some facts about Visible Light.

Answer 5

• We see it, as the colours of the rainbow
• Each colour has its own wavelength
• The only wave humans can see

Question 6

Give some facts about Ultraviolet Waves.

Answer 6

• Excessive amounts of UV light can cause cancer

- Some animals can see UV Rays

Question 7

Give some facts about X-Rays.

Answer 7

-Can travel through certain dense solids
-Prolonged exposure can cause burns and cancer
Example: Radiography (X-Rays)

Question 8

Give some facts about Gamma Rays.

Answer 8

-Most dangerous waves
-Waves can cause genetic mutations
-Can destroy harmful cells and bacteria
Example: Cancer treatment