radioactivit

Question 1

what is radioactive decay

Answer 1

nuclei spitting out radioactive decay ramdomly.

Question 2

background radiation

Answer 2

radiation from out of earth, sun
radiations due to human activit, e.g. from fallout of a nuclear explosion
substances here on earth.

Question 3

ionisation

Question 4

alpha particles

Answer 4

least penetrating ion
most ionising ion
made of 2 protons and 2 neutrons

Question 5

gamma rays short wavelength

Answer 5

no mass
weakly ionising
very penetrating

Question 6

beta particles

Answer 6

causes a neutron to turn into a proton and an electron

Question 7

medical tracers used in radioactivity

Answer 7

beta or gamma will pentrate the skin and other body tissues, radiation can be detected externally as radiation penetrates the body tissue.

Question 8

what is irradiation

Answer 8

objects near a radioactive source are irradiated, they are exposed to radiation, this does not make it radioactive.

Question 9

contamination

Answer 9

if radioactive atoms get onto an objects, these atoms may start to decay damaging the person by releasing radiation towards it.

Question 10

what happens when radiation enters your body,

Answer 10

when it enters it can collide with molecules in your cells these cause ionisation which damages or destroys your cells.

Question 11

fuel rods 
control rods
moderator 
shielding
do what and what are they made of

Answer 11

fuel rods made of uranium emit neutrons
control rods made of boron absorb
moderator slows down neutrons , grpahite or water
shielding, thick concrete structure, absorb ionising radiation

Question 12

fission reactions

Answer 12

slow moving neutrons absorbed by a nucleus this causes the nucleus to split.
spits out neutrons they go on to cause further fission

Question 13

exam question notes

Answer 13

for detector question it is gamma

iodine is a good medical tracer, penetrative so detected outside of body, not damaging to cells like beta.