Topic 5 Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

Which are the most energetic and the most dangerous waves

A

The ones with the highest frequencies (shortest wavelengths) are the most energetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Dangers of gamma rays and X-rays

A

Can cause mutations (changes) to the dna in the cells in the body

Could kill cells or cause cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Dangers of ultraviolet

A

UV in sunlight can damage skin cells, causing sunburn

Overtime exposure to UV can cause skin cancer

UV can also damage the eyes leading to eye conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Infrared dangers

A

Infrared radiation transfers thermal energy. Too much infrared radiation can cause skin burns

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Dangers of microwaves

A

Heat water
So they can the water inside our bodies
Heating cells can damage or kill them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Use of gamma rays

A

To sterilise good and medical equipment

In scanners to detect cancer

To treat cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Use of x rays

A

To look inside objects including medical x-rays to look inside bodies

In airport security scanners, to see what people have in their luggage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Use of ultraviolet

A

To detect security marks made using special pens

Inside fluorescent lamps

To detect forged banknotes

To disinfect water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Use of visible light

A

Allows us to see, lights up rooms and streets, building and roads

Photography

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Use of infrared

A

In cooking (by girls and toasters)

To make thermal images (images using heat) used by police and rescue services

In short range communications such as between laptops or other small computers

In remote controls for TVs and other appliances where the signal only has to travel short distances

To send information along optical fibres

In security systems such as burglar alarms to detect pills moving around

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Used of microwaves

A

In mobile phones, and to communicate by satellite transmissions

For cooking (in microwave ovens)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Used of radio waves

A

Broadcasting radio and TV programmes

Communicating with ships, aeroplanes and satellites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Radiation is absorbed or emitted when

A

Electrons jump between energy levels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Electrons can only exist in atoms at certain

A

Well defined energy levels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What do the energy levels in atoms depend on

A

Depend on the atom and the electrons inside the atom can move between the shells or leave the atom completely

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Electromagnetic radiation is emitted or absorbed by atoms based on wether

A

Energy is given out of taken in

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Electrons move up energy levels when they

A

Absorb energy and they fall down to lower energy levels when they emit energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Electrons move from a lower energy to a higher energy level when

A

The correct amount of energy is absorbed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Electromagnetic radiation is emitted when electrons

A

Fall down from a higher to a lower energy level

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Where can energy also be emitted from?

A

The nucleus of unstable atoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What do protons and neutrons also occupy

A

Energy levels in the nucleus in the same way tht electrons do in the atom

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

When energy changes occur in the nucleus

A

High energy gamma rays are emitted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Gamma-rays can be emitted over a large range of frequencies depending on

A

The energy levels within the nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Explain the energy changes that occur within the electron levels of the atom

A

Electrons can move between energy levels if they absorb or emit electromagnetic radiation

When they absorb electromagnetic radiation they move up energy levels and when they emit electromagnetic radiation they move down energy levels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

The energy of electromagnetic radiation that is emitted or absorbed has to match the

A

Difference between the energy levels that the electron is moving between

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Which energy changes are greater the ones in the nucleus or this seen between electron energy levels

A

In the nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Atoms have a nucleus containing

A

Protons and neutrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What move around the nucleus of the atom

A

Electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Protons =

A

Electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

+ charged =

A
  • charges so no overall charge
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

All atoms have a

A

Nucleus

32
Q

What charge has a nucleus for

A

Positive because it contains protons which have a positive charge

And neutrons which don’t have a charge

33
Q

The nucleus contains how much mass of the overall atom?

A

More than 99%

34
Q

Total number of protons in an atoms nucleus must be the same as th

A

Total number of electrons in the shapes

35
Q

Electrons in atoms always

A

Orbit the nucleus and have a negative charge

36
Q

Atoms are always

A

Neutral because the pos cancels out the neg charge from the electrons

37
Q

Nucleus of an atom of an Element my contain different numbers of

A

Neutrons

38
Q

What’s a molecule

A

Two or more atoms bonded together

39
Q

A molecule is about ___ times the diameter of an atom and about _____ times the diameter of a nucleus

A

10

10^6

40
Q

Gases such as ________ are molecules

A

Oxygen and carbon dioxide

41
Q

What is water

A

A molecule

42
Q

Diameter of an atom is about

A

10^-10

43
Q

Diameter of the nucleus is about

A

10^-15

44
Q

All atoms of a particular element have the same number of

A

Protons

45
Q

The number of protons in each atom of an element is called the

A

Atomic number or proton number

46
Q

Protons and neutrons in an atom is the

A

Mass number of nucleon number

47
Q

Atoms of a particular element always have the same number of protons but different numbers of

A

Neutrons

48
Q

Atoms with the same number of protons but different number of neutrons are

A

Isotopes of the same element

49
Q

What determines an element

A

Number of protons

50
Q

What can electrons do

A

Move between energy levels, or they can leave the atom completely

51
Q

An electron will move from a lower to a higher orbit if

A

It absorbs electromagnetic radiation

52
Q

An electron will move from a higher to a lower orbit if it

A

Emits electromagnetic radiation

53
Q

Electrons can leave an atom by:

A

Absorbing electromagnetic radiation of enough energy so that they can escape the pull of the nucleus
The three types of electromagnetic radiation that have enough energy to do that are UV, X rays and gamma rays

Being hit by a particle such as an alpha particle or beta particle

54
Q

Alpha beta gamma and neutron radiation are emitted by

A

Unstable nuclei

55
Q

What’s the process of nucleus decay

A

Tcompletely random so it’s not possible to determine exactly when

56
Q

Some elements are radioactive because their

A

Nuclei are unstable

57
Q

What does it mean having an unstable nuclei

A

They will undergo radioactive decay and change into other elements

58
Q

Unstable nuclei will decay when

A

Alpha beta gamma or neutron radiation is emitted

59
Q

An alpha particle is a

A

Helium nucleus
It is composed of two protons and two neutrons it has a charge of +2 and is the heaviest of the particles emitted by unstable atoms

60
Q

What’s a beta particle

A

An electron

61
Q

What charge does an electron have

A

-1

62
Q

A positron is an

A

Anti-electron and has a charge of +1

63
Q

A gamma ray is a form of

A

High-energy electromagnetic radiation. It has no mass or charge

64
Q

Charge of a neutron

A

Zero

65
Q

Alpha and beta particles and gamma-rays can collide with atoms which

A

Ionises then by causing them to lose electrons

66
Q

Properties of radiation

Neutrons:

A

Not directly ionising

Have a very high penetrating power due to them having no charge and not interacting strongly with matter

Can travel through humans and building for long distances before being stopped

67
Q

Alpha particles

A

Will travel around 5cm in air

Very ionising

Can be stopped by a sheet of paper

68
Q

Beta particles

A

Will travel a few metres in air

Moderately ionising

Can be stopped by aluminium

3mm thick

69
Q

Gamma rays

A

Will travel a few kilometres in air

Weakly ionising

Need thick lead to stop them

70
Q

Low levels of radiation are present around you…

A

All the time

71
Q

What’s background radiation

A

Both natural and man made

72
Q

Background radiation is exposing us to

A

Ionising radiation

73
Q

Background radiation is made up of many things such as

A

Ground and buildings

Medical

Nuclear power

Cosmic rays

Other

Food and drink

Random gas

74
Q

What can be used to measure and detect radiation?

A

Photographic film and a Geiger-müller tube

75
Q

What is the Geiger-müller tube

A

Is used to detect nuclear radiation

It is connected to a counter or rate meter which shows the amount of radiation that has been detected

76
Q

Detecting radiation

A

In 1896 henri becquerel discovered that uranium sky’s would lead to the darkening of a photographic film even if it was wrapped up so that no light could reach it

Radiation was being emitted from the uranium nuclei and this was responsible for the darkening of the film this is now made use of in the nuclear industry as workers will wear a film badge to determine if they are being exposed to different forms of nuclear radiation