5.2 Uses Of Electromagetic Waves

Question 1

What are electromagnetic waves

Answer 1

Electromagnetic waves consist of oscillating electric and magnetic fields. All electromagnetic waves travel through a vacuum at 3.0 x 10^8. Electromagnetic waves transfer energy from sources to absorbers.

Question 2

Radio waves

Answer 2

• tv and radio stations transmit television and radio signals by adding sound and picture information to radio waves.

Question 3

Micro waves

Answer 3

• microwaves are used to communicate with satellites, and for Wi-Fi and Bluetooth systems.
• food absorb as microwave radiation from microwave ovens to heat up.

Question 4

Infrared

Answer 4

• remote controls use pulses of infrared to communicate with televisions.
• you can send information at high speeds using infrared.

Question 5

Visible light

Answer 5

• ships sometimes communicate using flashing visible light.
• laser in CDs, DVDs and Blu-ray Discs use visible light.

Question 6

Ultraviolet

Answer 6

• helps to produce vitamin D
• kills bacteria in water

Question 7

X-rays

Answer 7

• detect bone fractures and certain tumours
• can kill skin cancer or other cancer cells

Question 8

Gamma rays

Answer 8

• sterilising food and medical equipment.
• kill cancer cells