P12 - Electromagnetic waves

Question 1

What are electromagnetic waves?

Answer 1

Transverse that can travel through a vacuum and are vibrations in electric and magnetic fields

Question 2

What does increasing the frequency y do to the wavelength?

Answer 2

Decreases it - inversely proportional

Question 3

What has a higher frequency radio or gamma?

Answer 3

Gamma

Question 4

What has a higher wavelength radio or gamma?

Answer 4

Radio

Question 5

What happens to size when you go from radio waves to gamma waves in the electromagnetic spectrum?

Answer 5

Size decreases

Question 6

Define a carrier wave?

Answer 6

Waves that can carry any type of signal

Question 7

What does a shorter wavelength affect?

Answer 7

More info carried
Shorter distance travelled
More dense

Question 8

Are microwaves or radio waves used for satellites?

Answer 8

Microwaves as they can pass through the atmosphere

Question 9

What is an alternating current?

Answer 9

Same frequency as voice is it supplied to a transmitter

Question 10

What do electrons in a transmitter do?

Answer 10

Oscillate, creating waves and transferring energy to electrons within it

Question 11

What are optical fibres?

Answer 11

Thin glass fibres that are totally internally reflected transmitting lots of info in a short wavelength and are more secure as signals stay in fibre

Question 12

Process of X -rays?

Answer 12

Pass through soft tissue and absorbed by bones showing up white, lead apron is required to prevent radiations as gamma can only be stopped by lead

Question 13

What is a contrast medium used for?

Answer 13

So we can see x - ray soft tissue allowing internal surfaces to show