Electromagnetic Waves

Question 1

What are EM waves

Answer 1

1. Radio waves
2. Microwaves
3. Infrared radiation
4. Visible light
5. Ultraviolent radiation
6. X-rays
7. Gamma rays

Question 2

Properties of EM waves

Answer 2

• EM waves can travel in a vacuum
• They travel at 3 x 10^8 m in vacuum
• They transfer energy from one place to another

-When EM waves travel from one medium to another, its speed and wavelength changes, frequency does not change

Question 3

Radio waves (skip to ans)

Answer 3

• Longest wavelengths
• Used in radios, communication, over-the-air tv
• Lowest frequency

Question 4

Microwaves (skip to ans)

Answer 4

• Used in microwave ovens, satellite tv and GPS

Question 5

Infrared radiation (skip to ans)

Answer 5

• Used in remote controls, ear thermoemeters and intruder alarms

Question 6

Visible light (skip to ans)

Answer 6

• Used in optical fibres

Question 7

Ultraviolet radiation (skip to ans)

Answer 7

• Used in sunbeds and sterilisation
• Prolonged exposure to UV can cause sunburn and cancer

Question 8

X-rays (skip to ans)

Answer 8

• Used in radiation therapy, imaging and detection of flaws in heavy metal equipment
• Used in X-ray machiones that check luggauge at airports

Question 9

Gamma rays (skip to ans)

Answer 9

• Shortewst wavelengths
• Used in radiation therapy
• Highest frequency