EM spectrum

Question 1

radio waves

Answer 1

• TV, radio, bluetooth

- low energy waves, not harmful

Question 2

microwaves

Answer 2

• satellite communications

- travel in straight lines

Question 3

infrared

Answer 3

• electrical heaters, food

- absorber in food and converted back into heat

Question 4

visible light

Answer 4

-fibre optic communications

Question 5

ultraviolet

Answer 5

• energy efficient light bulbs, sun beds
• UV waves are produced by gas in bulb when it is excited by electric current, then these waves are absorbed by coating on bulb which giving out visible light

Question 6

x rays

Answer 6

• medial

- penetrate soft tissue but not bone

Question 7

gamma rays

Answer 7

• sterilising food, treats tumours

- destroys bacteria

Question 8

radio waves can be caused by oscillations in

Answer 8

electrical circuits

Question 9

the frequency of the radio wave produced matches

Answer 9

frequency of electrical oscillations (this is how a radio signal is produced)

Question 10

when radio waves are absorbed by a conductor they may create

Answer 10

an alternating current with the same frequency as the radio wave (this is how signals are received)

Question 11

electrons moving between energy levels as a result of heat or electrical excitation can generate

Answer 11

waves

Question 12

changes in the nucleus of an atom can generate

Answer 12

waves eg unstable nucleus can give out excess energy as gamma rays