1
Q
what 3 things make up an atom
A
proton
nuetron
electron
2
Q
location, mass and charge of a proton
A
nucleus
1
positive +1
3
Q
location, mass and charge of a nuetron
A
nuclues
1
neutral
4
Q
location, mass and charge of a electron
A
obiting nuclues
almost 0
negative -1
5
Q
3 types of radiation
A
alpha, beta, gamma
6
Q
composition and charge type of alpha
A
helium nuclus(2 protons, 2 nuetrons)
positive +2
7
Q
composition and charge type of beta
A
high energy fast moving electron
negative -1
8
Q
composition and charge type of gamma
A
EM wave
no charge 0
9
Q
ionisation
A
when an atom gains or loses an electron
10
Q
what happens when a atom loses an electron
A
it will have an overall positive charge
11
Q
what happens when a atom gains an electron
A
it will have an overall negative charge
12
Q
ion
A
atom that has lost of gained an electron
13
Q
range and ionising power of alpha
A
few cm
high
14
Q
range and ionising power of beta
A
10s of cm
moderate
15
Q
range and ionising power of gamma
A
long
low almost 0
16
Q
does alpha pass thru paper
A
no
17
Q
does beta pass thru paper
A
yes
18
Q
does gamma pass thru paper
A
yes
19
Q
does alpha pass thru aluminium
A
no
20
Q
does beta pass thru aluminium
A
no
21
Q
does gamma pass thru aluminium
A
no
22
Q
does alpah pass thru lead
A
no
23
Q
does beta pass thru lead
A
no
24
Q
does gamma pass thru lead
A
no
25
geiger muller tube
two electrons, cental rod and outer cylinder, between which a 400V is applied
it is filled with low pressure gas
radiation enters thru thin mica whindow allowing gas to ionise letting ions complete the circut
send pulse of electricity whihc can be counted on electronic scaler or ratemeter
26
film badge
photographic film is placed inside
two windows of different thickness to tell what kind of beta radiation
3 different metals allowing detection of gamma rays and other ionising materials
final exposure shows what kind of radiation and how much a worker has been exposed to
27
activity
activity of a radioactive source is a measure of how many atoms decay radioactively every second
28
equation for activity
A=N/T
A= activity (Bq)
N=number of decays
t=time(s)
29
what does Bq mean
1 radioactive decay every sec
30
what does KBq mean
1000 radioactive decays per sec
31
what does Mbq mean
Million radioactive decays every sec
32
halflife
time taken for the activity of a radio active source to fall by half its original value
33
how to calculate half life from a graph
idenitfy the starting activity
find the activity that has half this value
find the time from the graph for this change to happen
34
how to find half life numerically
divide the inital activity by two and repeat until required value is reached
the number of times it has been divided is the number of half lives
total time / number of halflifes
35
absorbed does
measure of how much energy is absorbed per unit mass
36
equation for absorbed dose
D=E/m
D= absorbed does (Gy)
E= energy per unit mass(J)
m= mass (kg)
37
equivlent does
absorbed dose multiplied by a radiation weighing factor to take into account the level of ionisation
38
equation for equivilent does
H=DxWr
H= equivlent dose (Sv)
D= absorbed does (Gy)
Wr= radiation weighing factor
39
what does 1 Gy equal
1 J/Kg
40
equivlent dose rate
equivelent does recived per unit of time
41
equation for equivlent does rate
H(dot) = H/t
H(dot)= equivlent dose rate (Svh-1)
H= equivelnt dose (Sv)
t=time
42
natural background radiation
radon gas 40%
rocks & building materials 15%
cosmic rays 12%
food & drink 15%
43
artificial background radiation
medical 16%
nuclear power & weapons testing 1%
other 1%
44
treatment of cancer
high doses of radiation (gamma) kills cancer cells or slows their growth by damiging their Dna.
cancer cells stop dividing and die
45
sterilisation of medical equipment
exposed to high intsetiy gamma source which kills micrograms and bacteria
46
radioactive tracers
radioactive source with short halflife, emmits gamma rays thru body to detector which tracks the radiation
47
pipeline leak detectors
gamma ray emmiting source put into pipe and where there is a like the gamma rays would leak and be detected by a geiger muller tube
48
carbon dating
carbon 14 form of beta radiation that living orgamsims absorb into their tissue,
when they die absorpbtion stops and carbon 14 changes into other atoms due to half life
scientests can measure how much carbon 14 remains to estomate how old the thing is
49
nuclear power station work
radiation is emmited by the fuel heating water which is convertuted to stean driving a turbine which turns a generator generating elctricity
50
fission
large nuclous splitting into two or smaller nuclei realsing energy, used commercially
51
funsion
two small nuclei joining together to make a larger nucleus relasing energy
isn't used commercially
52
fission chain reaction process
a slow movign neutron collides with Uranium 235 nucleus
causes nucleus to divide into two or more daughter elements
causes large release of energy as well as 2-3 neutrons
each of these neutrons then collide with a further uranium nuclei
53
nuclear reactor
energy released by fission heats water which is converted into steam
steam drives turbine turning generator generating electricty
control rods absorbs neutrons controlling the rate of the reaction
54
nuclear fission
process which starts use as an energy source, converting hydrogen to helium
deuterium + tritium (isotopes of hydrogen)
= helium + nuetron
55
benefits of using fusion
fuel souce is hydrogen from water
waste product is helium which is not radioactive
produces more energy than fission
reactors have no risk of meltdown
56
problems with fusion
maintaing temp is very difficult
containg the plasma is difficult as all physical containers would melt
at present reactors not efficent enough to be commercially used
Physcis N5
flashcards
Decks in class (7)
# Cards
