CP5

Question 1

What type of wave are all EM waves?

Answer 1

Transverse

Question 2

What is the speed of all EM waves in a vacuum?

Answer 2

300,000 m/s

Question 3

What can be used to split white light?

Answer 3

Prism

Question 4

How was infrared discovered?

Answer 4

Herschel placed thermometers in a spectrum and noted the temperatures (red = hottest). He then placed a thermometer past the red end and noted that was even hotter so concluded there had to be a wave there – this was infrared

Question 5

What happens to the frequency and energy as the wavelength becomes shorter on the EM spectrum?

Answer 5

Shorter wavelength = higher frequency and more energy

Question 6

How are radiowaves produced and detected?

Answer 6

Produced and detected by oscillations (vibrations in electrical circuits);

Question 7

Explain why some telescopes are placed outside the Earth’s atmosphere

Answer 7

So they can detect parts of the EM spectrum blocked by the atmosphere. Also to avoid interference from clouds / weather conditions

Question 8

Microwaves

Answer 8

Communication
Cooking

Heat water in body cells

Question 9

Infared

Answer 9

Cooking
Remote controls
Night vision
Skin burns

Question 10

Visible

Answer 10

Photography
Sight

None

Question 11

Ultraviolet

Answer 11

Security marking
Sterilising water

Skin damage / cancer
Cataracts

Question 12

X rays

Answer 12

Security scanning
Medical imaging

Cancer

Question 13

Gamma

Answer 13

Sterilising medical equipment
Detecting and treating cancer

Cancer