background radiation, contam and irridation, nuclear Flashcards
(23 cards)
what is radioactive contamination
the unwanted presence of materials containing radioactive atoms on other materials. the materials then become a source / radioactive
what is the hazard of contamination caused by
the decay of contaminating atoms
whats irridation
the process of exposing an object to nuclear radiation, but the object doesn’t become radioactive / a source
name natural sources of background radiation
rocks, cosmic rays from space, food
name man made sources of background radiation
fallout from nuclear weapon testing and nuclear accidents, medical rays
what can the level of background radiation + radiation dose be affected by
occupation and / or location
whats radiation measured in
sieverts (Sv)
contamination
when a person has radioactive material in/on them
lasts for a long time
source of radiation is transferred to object (they become radioactive)
hazard of contaminated atoms
they decay releasing radiation
example of contamination
radioactive dust settling onto your skin - becomes contaminated
irridation
lasts for a short period of time
is exposed to radiation but doesn’t become radioactive
causes ionisation but doesn’t pose any risks
example of irridation
radioactive dust emitting beta radiation which irridates ur skin
hazards of irridation
irradiation can cause harm, contamination has the potential to cause far more harm, due to the continuous exposure to radiation that it will produce
hazards of contamination
dangerous if a radioactive source gets into the human body
The internal organs will be irradiated as the source emits radiation as it moves through the body
why are medical items sometimes irridated
to kill bacteria on its surface but not to make the tools themselves radioactive
why should scientifc reports be peer reviewed
if initial studies/measurements are wrong, it could cause peole to die
to make sure no one is harmed and it works effectively and its safe
what is nuclear fission
the splitting of a large unstable nucleus eg. uranium and plutonium
why is spontaneous fission rare
for fission to occur, the unstable nucleus has to absorb a neutron first
what does a nucleus undergoing fission split into
two smaller nuclei (roughly equal in size)
and emits two or three electrons and gamma rays
energy is also released
what do all fission products have
kinetic energy
what happens when a chain reaction is uncontrolled
an explosion
whats nuclear fusion
the joining of two light nuclei to form a heavier nucleus
sometimes mass is converted into the energy of radiation
advantages of nuclear power compared to use ofshale gas
nuclear power: doesn’t emit carbon dioxide, doesn’t cause global warming, doesn’t cause earthquakes, releases more energy per kg of fuel