Studied by 5 people
unstable nuclei
emits radiation and decays
ionising radiation
passes through matter and knocks electrons from atoms, leaving positive ions
why is ionising radiation dangerous
can damage DNA in living tissue and cause cancers
alpha radiation
high mass (4), high charge (2+), highly ionising with short range/low penetrating power
beta radiation
(comprimises electrons from nucleus) medium ionising, medium/medium penetrating power
gamma radiation
compromises a packet of high frequency electromagnetic radiation, low ionising, long range/high penetrating power
neutron decay
1 top, 0 bottom, n middle
whats stops each radiation
a: few sheets of paper, skin or cm of air/ b: few mm of aluminium/ g: few cm of lead of m of concrete
what is radiation detected with
geiger counter (becquerels)
half life
time it takes for the activity to fall by half
irradiation
when you exposed to radiation from a source outside the body
contamination
when radiation is inside or on a surface
where does background radiation come from
cosmic rays, radioactive radon gas leaking from ground
radiation in medicine
tracers, b or y used to treat cancer
nuclear fission
splitting nucleus in 2, dangerous as releases a lot of energy
nuclear fusion
combining 2 positive nuclei - creates huge amounts of energy
radiation from atoms
electrons can absorb radiation and move into a higher shell, producing an absorption line
Note 
Flashcard (23)