P2

OCR 21st Century Science Revision P2

?
  • Created by: zoe
  • Created on: 20-05-13 19:17
A family of seven radiations...
The electromagnetic spectrum
1 of 20
A beam of electromagnetic radiation contains packets of energy called...
Photons
2 of 20
The higher the frequency of an electromagnetic radiation...
The more energy is transferred by each photon
3 of 20
The intensity of electromagnetic radiation is the...
Energy arriving at a square meter of surface per second
4 of 20
The intensity of a beam of radiation...
Decreases with distance
5 of 20
When a material absorbs radiation...
Heat is created
6 of 20
The amount of heat created in radiation absorption depends on...
The intensity of the radiation beam and the duration of the exposure
7 of 20
The decrease in the intensity of radiation with distance is due to these three factors...
Photons spread out as they travel, some photons are absorbed by particles in the substances they pass through and some photons are reflected and scattered by other particles
8 of 20
Ionising radiation is...
Electromagnetic radiation with a high photon energy
9 of 20
Ionising radiation can break molecules into bit called...
Ions
10 of 20
Three types of ionising radiation...
UV radiation, x-rays, gamma rays
11 of 20
Radiation damages cells by...
Heating the skin causing sunburn, ionising radiation can age skin, can mutate DNA that can cause cancer, radiation poisoning
12 of 20
Light radiation from the sun...
Warms the earth surface when absorbed and is used by plants during photosynthesis
13 of 20
A thin layer of gas in the earths upper atmosphere...
The ozone layer
14 of 20
The greenhouse effect...
Earth emits electromagnetic radiation into space, gases in the atmosphere absorb some of the radiation and keeps the earth warmer than it would normally be
15 of 20
Radiation emitted from the earth has a _______ ________ _________ than that emitted by the sun.
Lower principle frequency
16 of 20
The earths temperature is increasing this is known as...
Global warming
17 of 20
These can have many different values so it is hard to distinguish between noise and the original signal...
Analogue signals
18 of 20
These only have two states on and off so they can still be recognised despite any noise that's picked up...
Digital signals
19 of 20
Two advantages of digital signals...
Information can be stored on a memory stick, information can be processed by computer
20 of 20

Other cards in this set

Card 2

Front

A beam of electromagnetic radiation contains packets of energy called...

Back

Photons

Card 3

Front

The higher the frequency of an electromagnetic radiation...

Back

Preview of the front of card 3

Card 4

Front

The intensity of electromagnetic radiation is the...

Back

Preview of the front of card 4

Card 5

Front

The intensity of a beam of radiation...

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Science resources:

See all Science resources »See all Physics resources »